          United States Court of Appeals
                     For the First Circuit


No. 13-2305

                    UNITED STATES OF AMERICA,

                            Appellee,

                               v.

                      EDISON BURGOS-MONTES,

                      Defendant, Appellant.



          APPEAL FROM THE UNITED STATES DISTRICT COURT

                 FOR THE DISTRICT OF PUERTO RICO

        [Hon. Jay A. García-Gregory, U.S. District Judge]



                             Before

                       Lynch, Chief Judge,
               Howard and Kayatta, Circuit Judges.



          Rachel Brill for appellant.
          Francisco A. Besosa-Martínez, Assistant United States
Attorney, with whom Rosa Emilia Rodríguez-Vélez, United States
Attorney, and Nelson Pérez-Sosa, Assistant United States Attorney,
Chief, Appellate Division, were on brief, for appellee.



                          May 13, 2015
             KAYATTA, Circuit Judge. Edison Burgos-Montes ("Burgos")

appeals from his conviction for two counts of drug conspiracy and

two counts of murder.       The latter stem from the disappearance of

Burgos' girlfriend Madelin Semidey-Morales ("Semidey") shortly

after Burgos learned that she had been acting as a government

informant.     Although the government sought the death penalty, the

jury sentenced Burgos to life in prison. Burgos now challenges his

conviction on a large number of grounds. For the reasons described

in this opinion, we affirm the district court in full.

                              I.   Background

             In this appeal, Burgos challenges the sufficiency of the

evidence supporting his conviction, the denial of several pre-trial

motions to suppress evidence, and a number of other district court

actions before and during trial.        We typically recite those facts

relevant to sufficiency claims and challenges to a denial of a

motion to suppress in the light most favorable to the verdict or to

the district court's ruling.       See United States v. Bayes, 210 F.3d

64, 65-66 (1st Cir. 2000) (sufficiency); United States v. Soares,

521 F.3d 117, 118 (1st Cir. 2008) (suppression). For other issues,

such   as   claims   of   prejudicial   error,   we   offer   a   "balanced"

treatment, see United States v. Felton, 417 F.3d 97, 99 (1st Cir.

2005), in which we "objectively view the evidence of record."

United States v. Nelson-Rodríguez, 319 F.3d 12, 23 (1st Cir.




                                    -2-
2003).1   Given that we cannot simultaneously recite the facts in

both manners, we limit our initial summary of this lengthy record

to those details essential to framing the issues on appeal.     We

then offer the key facts relevant to each issue as part of our

discussion of that issue, recited in the appropriate form.   We do

the same for the standard of review for each issue.

           In October 2004, Semidey agreed to work with agents of

the federal Drug Enforcement Administration ("DEA") to inform on

Burgos.   Semidey had begun dating Burgos while her husband was in

jail, and she continued to do so after her husband was released.

Over the next nine months, Semidey moved in with Burgos and

provided information to the DEA, arranged a meeting in which

undercover officers negotiated a cocaine sale with Burgos (although


     1
       In doing so, we note that this circuit has been inconsistent
in its approach to reciting the facts of the case when considering
a challenge other than the sufficiency of the evidence to support
a conviction. See United States v. Rodríguez-Soler, 773 F.3d 289,
290 (1st Cir. 2014) (discussing the inconsistency). Generally,
though, the nature of the question on appeal and the applicable
standard of review should make self-evident whether an appellate
court should present the record largely in equipoise (for example,
when it is assessing how an added or omitted item may have tipped
the balance, see Felton, 417 F.3d at 99), or present the evidence
as if the factfinder favored the prosecution's side of any factual
disputes (to ascertain, for example, whether the evidence was
sufficient to sustain the conviction, see United States v. Ayala-
García, 574 F.3d 5, 8 (1st Cir. 2009)), or assume that the jury
could well have been persuaded by the defendant's side of such
disputes (to ascertain, for example, whether the failure to submit
an element of the offense to the jury requires reversal in the
absence of any objection to the failure, see United States v.
Georgacarakos, 988 F.2d 1289, 1294-97 (1st Cir. 1993), abrogated on
other grounds by United States v. Scott, 270 F.3d 30, 35 (1st Cir.
2001)).

                                -3-
the sale was never consummated), and recorded conversations between

herself and Burgos.        In these conversations, Burgos described,

among other things, techniques for importing cocaine from the

Dominican Republic to Puerto Rico, and the prices he generally

charged for kilogram-quantities of cocaine.             According to trial

testimony, sometime around June 2005, one of Burgos' employees told

Burgos   that    Semidey   was   an   informant,    a   claim   that     Burgos

investigated     and   confirmed.     Semidey    also   told    her    handlers

(according to her handlers) that Burgos had threatened to kill her

over this rumor, and suggested that if she ever disappeared, agents

should look for her body on a "farm" that Burgos owned.               On July 4,

2005, Semidey disappeared after telling her handler that she had

returned to Burgos' house.       A witness at trial testified that she

last saw Semidey getting into Burgos' car on the night Semidey

disappeared.      Two days later, law enforcement agents observed

Burgos supervising an employee as the employee cleaned the inside

of Burgos' car during a rainstorm.

            After efforts to locate Semidey proved unsuccessful, DEA

agents sought and received the authorization to wiretap Burgos'

cell phone in September 2005.               In December, DEA agents also

recruited    a    co-conspirator       named     Neftalí   Corales-Casiano

("Corales") to work as an informant.             He recorded a number of

telephone calls between himself and Burgos between December 20 and

28.   Most incriminating was a December 28 conversation in which


                                      -4-
Corales said he was concerned that Semidey's body would be found,

to which Burgos replied, "It won't appear."               On December 29, the

government sought and received authorization to search Burgos'

farm, as well as the car that agents had observed Burgos having an

employee clean two days after Semidey disappeared.               The search of

the car revealed traces of blood that DNA analysis suggested was

Semidey's. Semidey never reappeared, and her body was never found.

            In January 2006, Burgos was indicted for conspiring to

import   and    conspiring   to     possess      with   intent   to   distribute

controlled substances in violation of 21 U.S.C. §§ 846, 841(a),

963, and 952.     The indictment described a conspiracy lasting from

1998 to 2005, and described a number of acts in furtherance of the

conspiracy that took place primarily between January and June 2005,

including      discussions   with       unindicted      co-conspirators   about

arrangements to purchase between one and ten kilograms of cocaine,

and stealing a boat.     A May 2006 superseding indictment added two

murder   counts,    stemming      from    Semidey's      disappearance.     The

indictment charged that Burgos had murdered Semidey to prevent her

from communicating with law enforcement and to retaliate against

her for communicating with law enforcement in violation of 18

U.S.C.   §§    1512(a)(1)(A)      and     (C),   and    1513(a)(1)(B).2      The




     2
       The indictment also included a forfeiture count that is not
at issue in this appeal.

                                         -5-
government also notified Burgos that it would seek the death

penalty.

           In the lead-up to trial, Burgos filed a number of motions

seeking to strike the death penalty, all of which were denied.   He

also filed numerous motions to suppress evidence.      Although the

district court granted some of his motions to suppress, it denied

both a motion to suppress the evidence obtained through the

wiretap, United States v. Burgos Montes, No. 06-009-01(JAG), 2010

WL 5184844, at *13 (D.P.R. Dec. 20, 2010), and a motion to suppress

evidence from the search of Burgos' car and farm. United States v.

Burgos Montes, No. Crim. 06-009 JAG, 2011 WL 1743420, at *1 (D.P.R.

May 2, 2011).

           After hearing thirty days of evidence, the jury convicted

Burgos on all four counts.   During the penalty phase of the trial,

Burgos raised allegations of possible juror bias.      The district

court held an in camera meeting with the juror in the presence of

counsel and determined that there was no bias, so the juror

returned to the box and the penalty phase continued.   On the basis

of this episode, Burgos filed a motion for acquittal or new trial.

He also moved for acquittal or new trial on the basis that the

evidence fell short of the minimum sufficient to convict.3       The


     3
       Burgos argued that there was insufficient evidence that
Burgos intended to kill Semidey because she was an informant, as
opposed to for some other reason. He also argued that the evidence
presented at trial constituted a fatal variance from that charged
in the indictment. The latter argument was also the basis of a

                                -6-
court denied both motions in a sealed order.           Because the jury

could not reach a unanimous verdict on the death penalty, Burgos

was sentenced to life imprisonment.

            Burgos filed a timely notice of appeal challenging: (1)

the denial of the motion to suppress evidence from the wiretap, (2)

the denial of the motion to suppress evidence from the search of

the car and farm, (3) the denial of the motion for acquittal or new

trial on the basis of alleged jury bias, (4) the denial of the

motions to strike the death penalty, (5) the denial of the motions

to acquit or for a new trial based on the sufficiency of the

evidence, and (6) various evidentiary rulings.

                              II.   Analysis

A.   Motion To Suppress Wiretap Evidence

            Burgos challenges the district court's denial, after an

evidentiary   hearing,   of   his   motion   to   suppress   a   number   of

conversations recorded through a wiretap of his cell phone after

Semidey disappeared. The wiretap was authorized under Title III of

the Omnibus Crime Control and Safe Streets Act of 1968, 18 U.S.C.

§§ 2510-22, which imposes a set of statutory requirements on top of

the constitutional requirements applicable to ordinary search

warrants.   See United States v. Nelson-Rodríguez, 319 F.3d 12, 32

(1st Cir. 2003).    Burgos advances four primary challenges to the

wiretap, which we address in turn.


mistrial motion that the district court denied in open court.

                                    -7-
        1.     "Omitted" Information About Semidey

               Burgos' first argument is that in the affidavit in

support of their wiretap application, the DEA agents omitted

information about Semidey that, had it been included, would have

precluded a finding of probable cause under the Fourth Amendment of

the United States Constitution.           In assessing such an argument

(assuming the omitted information was intentionally or recklessly

withheld), we ask whether the application, had it contained the

omitted information, would still have provided a "sufficient" basis

for authorizing the wiretap.4        United States v. Young, 877 F.2d

1099, 1102-03 (1st Cir. 1989) (citing Franks v. Delaware, 438 U.S.

154, 171-72 (1978)).

               The government's application for authorization to conduct

a thirty-day wiretap of Burgos' cell phone was supported by a

thirty-seven-page affidavit filed by DEA Agent Jacobsen, with the

participation of Agent Iglesias, who was the lead agent on the

case.        The affidavit described the investigation as being led by

the DEA and involving the FBI, the Puerto Rico Police Department,

and two Puerto Rico investigative units, the Hacienda and the NIE.


        4
       Young used several terms to describe the standard it was
applying to the reformed affidavit, including "adequate,"
"sufficient," and whether the omissions were "material" to a
finding of probable cause. 877 F.2d at 1102-04 There is nothing
to suggest the court intended the terms to convey different
meanings; indeed, its reliance on Franks makes clear it was
applying a sufficiency standard.      Franks, 438 U.S. at 171-72
(asking whether a reformed affidavit contained "sufficient content
. . . to support a finding of probable cause").

                                    -8-
In addition to Burgos, one of the five targeted individuals was

Corales, whom the affidavit described as a former police officer

who was fired for corruption allegations in 1997, and who had

multiple felony arrests and convictions between 1995 and 1998.

             The   evidence      supporting        the    affidavit       consisted     of

information from three confidential sources, including Semidey

(through her reports submitted prior to her disappearance).                            The

first two sources described the activities of named individuals

believed to be lower-level members of a drug trafficking conspiracy

that brought cocaine into Puerto Rico from the Dominican Republic.

The evidence connecting Burgos to drug trafficking came from or

through   Semidey.          According      to    the    affidavit,        she   described

conversations in which Burgos said he could procure large amounts

of cocaine.     She also helped arrange a meeting between Burgos and

undercover officers, which was recorded, and in which the officers

arranged a cocaine purchase.              Toll registers confirmed that Burgos

was in contact with the people that Semidey said he called to

discuss the planned sale to the officers.                     Burgos never delivered

any drugs, however.

             The application also described Semidey's statements that

Burgos suspected the undercover officers were officers and that he

had   confronted      her      with   a    rumor      that    she   was    cooperating.

According     to   the      affidavit,      Burgos       threatened       to    make   her

"disappear     from      the    earth."          It    also    described        Semidey's


                                           -9-
disappearance on July 4, 2005, and agents' observations of Burgos

supervising as an employee "rigorously" washed the interior of

Burgos' car during a rainstorm on July 6.

           The affidavit described Semidey as a paid informant who

was cooperating for personal reasons.             It then described her

observations of Burgos' drug activities, her role in helping to

arrange a failed buy-bust, the fact that Burgos had threatened her,

and her disappearance. "Omitted" from the affidavit were the facts

that Semidey was in a relationship with Burgos, that she was

married to another man who had been released from prison shortly

before she agreed to inform on Burgos, and that she may have been

trying to avoid prosecution on unrelated charges.5

           Nothing in these omitted facts materially undercuts the

affidavit's ample demonstration of probable cause.            The omitted

information furnishes, at best, grist for a somewhat conjectural

and by no means strong argument that one might make to discredit

Semidey.   None of this grist is so probative as to make its

omission particularly notable.       See Young, 877 F.2d at 1103 ("The

law does not require an officer swearing out an affidavit for a

warrant to include all possible impeachment material. It need only

explain that the officer has found the informant to be reasonably

reliable.").    We   note,   too,    that   key   portions   of   Semidey's


     5
       While there was trial testimony by Semidey's mother and
sister that Semidey agreed to be an informant to avoid possible
prosecution in another matter, the DEA agents involved denied this.

                                    -10-
statements in the affidavit were corroborated within the affidavit

itself.        The affidavit reflects that after Semidey introduced

Burgos to undercover agents, Burgos himself spoke with undercover

agents on at least three occasions regarding a potential cocaine

sale.       Moreover, toll records corroborated Semidey's descriptions

of Burgos' telephone communications about this potential sale.

               In sum, even had the affidavit included the omitted

information, the affidavit would easily have contained a sufficient

basis for concluding that a wiretap would produce evidence that

Burgos was involved in a drug conspiracy or murder.             Burgos'

challenge to the wiretap based on this "omission" of information

concerning Semidey therefore fails.6       Young, 877 F.2d at 1102.

        2.     "Omitted" Information About Corales

               Burgos' next argument trains on the so-called "necessity"

requirement of 18 U.S.C. § 2518(1)(c).        This subsection provides

that wiretaps are generally only available when the government

shows with a "full and complete statement . . . whether or not

other investigative procedures have been tried and failed or why

they reasonably appear to be unlikely to succeed if tried or to be

too dangerous."       Id.




        6
       Our conclusion that the affidavit contained a sufficient
basis to establish probable cause for the wiretap at the time of
the Title III application also disposes of Burgos' argument that
the information contained in the affidavit was "stale."

                                    -11-
          According to Burgos, the affidavit's claim that a wiretap

was necessary was deficient because it did not provide "full and

complete" information about Corales.   Specifically, Burgos argues

that the affidavit did not give any indication that Corales had

sometimes worked as an informant and could potentially be used as

one in this investigation.   Burgos argues that a wiretap could not

have been necessary until the government first tried to use Corales

as an informant.

          In considering a claim that improperly omitted facts

undermine the necessity of a wiretap, we use a similar approach to

that which we use to assess a claim that such omissions undermine

probable cause:    we ask whether, had the omitted information been

included, there would still have been a "minimally adequate" basis

for determining that the wiretap was necessary.7   See United States

v. Cartagena, 593 F.3d 104, 109-11 (1st Cir. 2010).

          The answer to this question is "yes."       The affidavit

explained why normal investigative techniques were not expected to

yield results. In particular, agents had twice tried and failed to

arrange a buy-bust, and using other informants was dangerous, given

what appeared to have happened to Semidey.         That explanation

provides more than adequate support for a conclusion that the

exigencies did not warrant further delay in order to try to recruit


     7
       We do not read the "minimally adequate" standard to differ
substantively from the sufficiency standard applied to a challenge
that omissions undermine probable cause. See footnote 4, supra.

                                -12-
yet another confidential informant, much less for what appeared to

be an exceedingly dangerous mission.            See 18 U.S.C. § 2518(1)(c)

(recognizing      that   some   investigative     techniques     may   be    "too

dangerous").       Whether Corales could have been recruited as an

informant (or even the fact that he later acquired his own reasons

to volunteer as an informant, as discussed in footnote 10 of this

opinion) is therefore beside the point.

     3.      Sealing Of The Wiretap Recordings

             We   now    turn   to   Burgos'   argument   that   the    wiretap

application failed to comply with certain procedural requirements

under 18 U.S.C. § 2518(8)(a).             That subsection provides that

"[i]mmediately upon the expiration of the period of the order"

authorizing a wiretap, "such recordings shall be made available to

the judge issuing such order and sealed under his directions." Id.

It further provides that "[t]he presence of the seal provided for

by this subsection, or a satisfactory explanation for the absence

thereof" is a prerequisite for any use of the evidence.                Id.

             Burgos makes two arguments:         (1) that the records were

not sealed "immediately," because the government ended the wiretap

on September 30 but the recordings were not sealed until October 7,

and (2) that they were not sealed by the same judge who had issued

the order.    The government does not dispute these deviations from

the statutory requirements.          It argues, however, that because it

has offered a "satisfactory explanation" for the late sealing, and


                                       -13-
because the use of a different judge is immaterial, the recordings

need not be suppressed.    After an evidentiary hearing to consider

the issue of sealing, the district court denied Burgos' motion to

suppress the wiretap evidence on these grounds.         Burgos Montes,

2010 WL 5184844, at *5-8.

            Before turning to the substance, we must first address

the threshold issue of the proper standard of review.          Neither

party points us to a standard of review for the question of whether

the government's explanation for the absence of a seal that

complies    with   the   requirements   of    section   2518(8)(a)   is

"satisfactory."    It appears that this circuit has never expressly

articulated one.    Other circuits are split, with some employing a

clearly erroneous standard, see, e.g., United States v. Coney, 407

F.3d 871, 874 (7th Cir. 2005), and others applying plenary review

to the question of whether the explanation is satisfactory, even

though subsidiary factual questions are reviewed for clear error,

see, e.g., United States v. Sawyers, 963 F.2d 157, 159 (8th Cir.

1992).     In United States v. Mora, 821 F.2d 860, 869-70 (1st Cir.

1987), which articulated the factors that define a "satisfactory

explanation" in this circuit, we accepted the district court's

supported subsidiary factual findings, but applied de novo review

to whether those facts were satisfactory under the newly announced

test.    We will follow in those footsteps.




                                 -14-
          In assessing the ramifications of an untimely sealing,

Mora established that the key inquiry was whether the government

had proven "by clear and convincing evidence that the integrity of

the tapes ha[d] not been compromised."   Id. at 867.   Sealing helps

ensure and demonstrate a lack of tampering.      To the extent that

there is any delay in sealing, the field may open more widely for

the defendant to question and explore what happened to the records

pre-sealing.

          Here, the district court concluded that Iglesias was

credible in his testimony that the "recordings were kept in a

manner that sufficiently excludes the possibility of tampering,"

and noted that Burgos had not even argued that they had been

tampered with.    Burgos Montes, 2010 WL 5184844, at *7.   On appeal,

Burgos again offers no allegations of tampering.   While the burden

of proof is on the government, this does not mean the government

must prove a negative when the defendant does not even allege that

tampering has taken place.    Burgos also does not offer any facts

speaking to the other factors in Mora, particularly indications of

bad faith by law enforcement personnel or prejudice to him--his

argument simply turns on the bare fact that seven days is not

"immediately."     However, in Mora itself, the court found that

delays of twenty and forty-one days, while concerning, did not

automatically require suppression in light of the other factors.

Id. at 869.      We conclude the same here regarding the seven-day


                                -15-
delay, given the lack of any evidence of tampering or other

possible prejudice, and the lack of evidence of bad faith.

          We can also quickly dispense with Burgos' objection to

the sealing of the recordings by a judge other than the one who

approved the wiretap.   When Iglesias took the recordings to the

issuing judge, he was told that the judge was unavailable and was

sent to a different judge, who sealed them.    Burgos cites no case

where recordings have been suppressed under such circumstances.

Few cases have addressed the issue at all, although the Second

Circuit has suggested in dictum that when the issuing judge's

unavailability would result in a delay, sealing by a non-issuing

judge is permissible.   United States v. Poeta, 455 F.2d 117, 122

(2d Cir. 1972).   As a purely textual matter, the agents appear to

have complied with the statute in that they "made [the recordings]

available to the [issuing] judge" and followed her "direction[]" to

take them to a different judge for sealing.    Thus, this argument

also fails.

     4.   Miscellaneous Shots At The Warrant

          Burgos lobs a number of other arguments at the substance

of the affidavit, none of which give us significant pause.       He

argues that the affidavit was not full and complete because some

statements were too vague, and because it includes a one-sentence

disclaimer that the affidavit included only information relevant to

the wiretap application and not all of the information from the


                               -16-
entire investigation.      These arguments fail on the grounds that an

affidavit need not include the "minutiae" of an investigation. See

Cartagena, 593 F.3d at 110; see also United States v. Yeje-Cabrera,

430 F.3d 1, 9-10 (1st Cir. 2005).

             Burgos also complains that the affidavit's authorization

to include individuals "yet unknown" violates the requirement that

the application include "the identity of the person, if known,

committing     the    offense    and   whose   communications   are     to   be

intercepted."        18 U.S.C. § 2518(1)(b)(iv).       He argues that the

government knew the names of certain other individuals that would

eventually be recorded and failed to include them.                In United

States v. Donovan, 429 U.S. 413 (1977), the Court held that this

requirement     to    identify   individuals    extends   to    those   whose

conversations the government has probable cause to believe would be

intercepted.    Although it is typically the unnamed individuals who

challenge a wiretap under such circumstances, see id. at 428; see

also United States v. Chiarizio, 525 F.2d 289, 291-93 (2d Cir.

1975), we will assume without deciding that a named individual can

also bring such a challenge because it does not affect the outcome

here.8   Nevertheless, Burgos offers no facts establishing that the



     8
       While this would make little sense in the Fourth Amendment
context, where the named individual would be asserting the unnamed
individual's rights, in this context the named individual is
claiming that his conversations were recorded pursuant to a
statutorily deficient wiretap, even though it is difficult to see
how the deficiency could be prejudicial.

                                       -17-
government had probable cause to believe that the other individuals

would be intercepted on the targeted telephone, so this argument

also fails.

B.   Motion To Suppress Evidence From Burgos' Car And Farm

           Burgos next challenges on a number of grounds the denial

of his motion to suppress evidence seized from his car and farm

pursuant to a search warrant.   As with the wiretap warrant, Burgos

argues that the application for the warrant was deficient because

of omissions and inaccuracies in the application.   In considering

such a challenge, our approach is similar to the one we used with

regard to the wiretap:   "we excise the offending inaccuracies and

insert the facts recklessly omitted, and then determine whether or

not the 'corrected' warrant affidavit would establish probable

cause."   Burke v. Town of Walpole, 405 F.3d 66, 82 (1st Cir. 2005)

(quoting Wilson v. Russo, 212 F.3d 781, 789 (3d Cir. 2000)).9

Burgos also argues that the application did not satisfy the

"particularity" requirement of the Fourth Amendment.   In reviewing

the denial of a motion to suppress based on such a claim, we review

the district court's fact-finding for clear error, and conclusions

of law de novo.   United States v. Kuc, 737 F.3d 129, 132 (1st Cir.

2013).


      9
       While the rule applies to omissions made with intentional or
reckless disregard for the truth, see Burke, 405 F.3d at 81-82, we
need not decide whether or not the omissions here were reckless or
intentional, because either way, they do not undermine probable
cause.

                                -18-
     1.     "Omitted" Information About Corales and Semidey

            A warrant application must include sufficient information

to establish probable cause both that a crime has been committed,

and that evidence of the crime will be found in the place to be

searched.    United States v. Hicks, 575 F.3d 130, 136 (1st Cir.

2009).    Burgos argues that the application for the warrant was

deficient because it omitted material information undermining the

credibility of Semidey and Corales, whose statements comprised much

of the information in the affidavit.       Burgos again argues that the

affidavit did not explain the nature of Semidey's relationship with

Burgos or her potential motivations for serving as an informant,

nor the fact that Corales was a disgraced former cop with a history

of perjury and multiple felony convictions.

            The affidavit provided the following as a basis for

probable cause:

•           Semidey's statements to a DEA agent that Burgos had

            confronted her with a rumor that she was an informant,

            and had threatened to kill her;

•           Semidey's statements that if she ever disappeared, law

            enforcement should look for her on Burgos' farm;

•           Observations of Burgos having an employee "rigorously"

            wash the interior of his car in the rain two days after

            Semidey   disappeared    and   shortly   after   the   police

            contacted him with questions about Semidey;


                                    -19-
•         High call volume from Burgos' phone to Semidey's that

          stopped the night of her disappearance, followed by a

          single call to her number after the police contacted him

          about her disappearance;

•         Visual observations by Iglesias of "what appeared to be

          a   newly   turned   area     of   earth   in   the   approximate

          dimensions of a grave" on the farm;

•         A recording of a call between Burgos and co-conspirator

          Radamés Castillo-Martinez ("Castillo") in which Castillo

          said he was concerned that something might have happened

          to Burgos because of "this girl";

•         Statements by Corales and Castillo that Burgos knew

          Semidey was an informant;

•         Several     statements   by     Corales,   identified    in   the

          affidavit as "CS #2," recounting conversations in which

          Burgos said he was not concerned to hear that co-

          conspirator Castillo had been arrested because he was

          confident that the police were not going to find Semidey;

          that the DEA would have arrested him by then if it could;

          and that he didn't understand how Semidey could have

          "cause[d] damage" to him after he had paid her bills and

          her children's living expenses;10


     10
       Corales volunteered to serve as an informant in December
2005, after he learned that co-conspirator Castillo had been
arrested on charges related to their preparations to import cocaine

                                   -20-
•         A conversation between Corales and Burgos in which Burgos

          said that Semidey's body "won't appear" and that "[t]hey

          can look for her in Yauco, Ponce, and Mayaguez and

          they're not going to find her."        In the conversation,

          Burgos and Corales also made plans to bury a stolen boat

          on the farm.    (This conversation was recorded, although

          the affidavit does not make that clear.);

•         Corales' statement that he believed Semidey may be buried

          on the farm.

          This evidence clearly suffices to establish probable

cause, even considering the affidavit in light of the omitted

information   about   Semidey   and   Corales.   In   particular,    the

credibility of Semidey's statements that Burgos had threatened her

are not undercut by the kind of information that might cast doubt

on her credibility with regard to Burgos' drug activities.          When

informant Jane reports that target John threatened to kill her

because John learned that Jane is an informant, and Jane then

disappears after last being seen getting into John's car, after

which John is seen washing the car in a rainstorm, it almost goes

without saying that there exists probable cause to conduct further

investigations into John no matter what one thinks about Jane's

motives for serving as an informant. See United States v. Hibbard,

963 F.2d 1100, 1101-02 (8th Cir. 1992) (upholding a warrant


from the Dominican Republic.

                                 -21-
authorizing the search of defendant's residence for the whereabouts

of a missing person based entirely on the fact that the defendant

had threatened the victim and that the victim was last seen in the

defendant's presence).     Whatever additional corroboration such

statements might need is amply provided for by the recorded

conversation between Burgos and Corales in which Burgos stated that

Semidey was not going to appear.      In short, nothing in the omitted

evidence cast any material doubt on Semidey's statements relevant

to the warrant application.

          As   for   Corales,   the   corroborating   information   not

dependent on his credibility is sufficient to establish a nexus to

the car and the farm.   The search of the car was based primarily on

agents' observations of Burgos having the car's interior washed in

the rain two days after Semidey disappeared, and shortly after law

enforcement went to Burgos house to attempt to question him.         As

for the farm, the affidavit established a nexus based on Semidey's

statements that law enforcement should look for her body on the

farm if she disappeared, as well as the recorded conversation in

which Burgos and Corales agreed to bury a boat on the farm.     Thus,

even considering the affidavit in light of Corales' potential

unreliability, there is a sufficient basis for probable cause.

     2.   Other Probable Cause Arguments

          Burgos makes several other arguments for why the warrant

failed to establish probable cause.       First, he points to certain


                                 -22-
inaccuracies      in    the    warrant's      description           of   events.       In

particular, he argues that Iglesias' trial testimony regarding his

observations of disturbed earth on the farm appear to vary from his

description    in      the   affidavit.           As    discussed    above,   however,

probable    cause      existed      even   without        the   observation    of     the

disturbed earth, so we need not delve into this argument.                          As for

the car, Burgos attempts to build a probable cause challenge based

on the fact that the affidavit described Burgos washing the inside

of his vehicle with an employee, while testimony in the suppression

hearing    made   clear      that    Burgos       was    actually    supervising      the

employee and did not participate in the washing himself.                           Burgos

argues that having a third party wash the car is inconsistent with

an attempt to remove evidence of a crime, where one would expect

great secrecy.      However, the description of the car-washing in the

affidavit does indicate that a third party, who seemed to be

Burgos' employee, was involved, so this minor difference in how

Iglesias described the event is not material.

            Finally, Burgos makes a staleness argument based on the

passage of time between Semidey's disappearance in July 2005 and

the government's application for a search warrant in December,

after Corales agreed to cooperate.                      Burgos argues that even if

there was probable cause to believe that there had once been

evidence in the car, the affidavit did not include any reason to

believe that it would have still remained six months later.                            An


                                           -23-
allegation of staleness is evaluated not merely on how old the

information is, but circumstances including the nature of the

suspected crime, the character of the items to be seized, the

habits of the suspect, and the nature of the premises to be

searched.   United States v. Bucuvalas, 970 F.2d 937, 940 (1st Cir.

1992), abrogated on other grounds by Cleveland v. United States,

531 U.S. 12, 18 (2000).       Burgos cites no case where evidence was

suppressed on the basis of a failure to state the common-sense

notions that bodies often stay where they are disposed of, and that

DNA evidence can last longer than six months, and we decline to

announce such a rule here--particularly given that the passage of

time    without   Semidey's   reappearance     made   foul   play    appear

increasingly more likely.

       3.   Particularity

            Burgos next argues that the search warrant violates the

Constitutional    requirement    that   a   warrant   must   "particularly

describ[e] . . . [the] things to be seized."          U.S. Const. amend.

IV.    The warrant authorizes a search for "[e]vidence and trace

evidence relevant to the homicide of Madelin Semidey-Morales in

violation of Title 18, United States Code, Section 1513.            See also

the attached affidavit, which is hereby incorporated and made part

hereof."    Burgos argues that "evidence and trace evidence" is

insufficiently particular, and that the failure to define the kind

of "trace evidence" sought was particularly egregious because


                                  -24-
Iglesias admitted that he used the broad term precisely to avoid

limiting the forensic analysis.

          Although federal courts do not generally uphold warrants

authorizing the search for "evidence of crime X" unless that

statement follows a list of illustrative examples, see United

States v. Bithoney, 631 F.2d 1, 2-3 & n.1 (1st Cir. 1980), Burgos'

argument fails because the warrant incorporates by reference the

affidavit, which describes the target of the search as "the person,

or remains, of Madelin Semidey-Morales, evidence of the manner of

her death and her personal effects."        Affidavit language expressly

incorporated   by   the   warrant     can   satisfy    the   particularity

requirement.   See Rivera Rodríguez v. Beninato, 469 F.3d 1, 5 (1st

Cir. 2006); cf. Groh v. Ramirez, 540 U.S. 551, 557-58 (2004)

(collecting circuit cases allowing incorporation by reference and

leaving open the possibility of incorporation).         While there still

exists some generality in terms like "evidence of the manner of her

death" and "her personal effects," this is a situation in which the

"circumstances of the crime make an exact description of the fruits

and instrumentalities a virtual impossibility."          United States v.

Timpani, 665 F.2d 1, 5 (1st Cir. 1981) (quoting Spinelli v. United

States, 382 F.2d 871, 886 (8th Cir. 1967)).           In such cases, "the

searching officer can only be expected to describe the generic

class of items he is seeking."      Id. (quoting Spinelli, 382 F.2d at

886).


                                    -25-
        4.      Compliance With Rule 41(e)

                Burgos next attacks the warrant on the grounds that the

issuing magistrate failed to fill in two of the spaces on the pre-

printed warrant form:        one for the date by which the warrant was to

be executed, and one for the judge to whom the warrant should be

returned.        (The space on the form for the return date is followed

by the parenthetical "not to exceed 10 days.")              Burgos argues that

these        omissions   violate   Federal     Rule   of   Criminal    Procedure

41(e)(2)(A) (2009), which required the warrant to "command the

officer . . . to execute the warrant within a specified time not

longer than 10 days" and to "return the warrant to the magistrate

judge designated in the warrant," and that such violation mandates

suppression.11

                In United States v. Bonner, 808 F.2d 864 (1st Cir. 1986),

we considered a different subdivision of Rule 41, one providing

that officers must leave a copy of the warrant at the place to be

searched. See Fed. R. Crim. P. 41(f)(1)(c).12 We held that because

the subdivision is "ministerial," a violation does not require

suppression        unless   the    defendant   can    demonstrate     prejudice.

Bonner, 808 F.2d at 869.            Prejudice means being "subjected to a

search that might not have occurred or would not have been so


        11
       In 2009, Congress amended Rule 41(e), increasing to 14 days
the time to execute the warrant.
        12
             At the time Bonner was decided, the subdivision was numbered
41(d).

                                       -26-
abrasive" had the rules been followed.     Id. (internal quotation

marks omitted).   Other circuits have held the same applies to all

the prerequisites of Rule 41. See United States v. Schoenheit, 856

F.2d 74, 76-77 (8th Cir. 1988); United States v. Burke, 517 F.2d

377, 386-87 (2d Cir. 1975).

          We have little trouble concluding that the prejudicial

error rule of Bonner should extend to the failure by the issuing

magistrate to define the time period of the search when the form

itself provides that the search is to be completed within the time

frame specified by the rule, and to the failure to designate a

magistrate to whom the form should be returned. "The exclusionary

rule should be limited to those situations where its remedial

objectives are best served, i.e., to deter illegal police conduct,

not mistakes by judges and magistrates."   Bonner, 808 F.2d at 867

(citing United States v. Leon, 468 U.S. 897, 908, 916 (1984)).

Burgos does not suggest why he was prejudiced by the warrant's

technical failings.   Absent a showing of prejudice, there is no

basis for suppressing the evidence.13

     5.   Fruit Of The Poisonous Tree

          While serving as an informant, Semidey (against her

handlers' instructions) took a number of documents--including some


     13
        The warrant was executed in compliance with the 10-day
statutory maximum in effect at the time, and Burgos does not argue
it was not.    The warrant was issued on December 29, 2005; the
search of the farm took place on December 30 and 31, 2005, and the
search of the car took place on January 5, 2006.

                               -27-
pertaining to the farm--from Burgos' residence.        The physical

evidence of this unconstitutional search was suppressed.      Burgos

now argues that any evidence from the farm should be suppressed as

the fruit of the poisonous tree.       The district court denied the

motion to suppress on the grounds that a search of the farm was

inevitable.   See United States v. Scott, 270 F.3d 30, 42-45 (1st

Cir. 2001) (explaining the inevitable discovery doctrine).        On

appeal, Burgos argues in a single conclusory sentence that the

government has not met its burden of proving by a preponderance of

the evidence that the farm would have been discovered by lawful

means.   He does not challenge the specific evidence from which the

district court concluded that discovery was inevitable:          DEA

agents' conversations with Semidey and Corales, as well as an

instance where local police seized some stolen containers from the

property.     This argument, even if not waived for perfunctory

briefing, see United States v. Zannino, 895 F.2d 1, 16 (1st Cir.

1990), fails in the face of the evidence found persuasive by the

district court.

C.   Juror Bias

            We now turn to Burgos' claim that the district court

abused its discretion when it first failed to hold an evidentiary

hearing to investigate allegations of juror bias, and then failed

to grant a new trial on account of that alleged bias, all in

violation of Burgos' Sixth Amendment right to a trial by impartial


                                -28-
jury.        U.S. Const. amend. VI.   This claim arises out of an incident

during the sentencing phase of trial in which a juror appeared to

slump in his chair when a man we will call Juan walked into the

room.        Juan was married to one of the witnesses who testified for

the defense in the penalty phase.             At the next break, Juan told

defense counsel that he was a second cousin of the juror (their

grandmothers were sisters).           Defense counsel told the judge that

the juror was appearing to hide from Juan.

                The judge held an in camera meeting in which he asked the

juror if he recognized anyone in the court room that day.              The

juror said he had not recognized anyone "involved in the case," and

stressed that if he recognized anyone, he would speak up.14            The

district court asked several more times (e.g., "So far in the case,

you haven't recognized anybody?").            To each question, the juror

responded that he had not, and that "[i]f I . . . recognize

somebody, I will tell the Court.         But I didn't."   He also explained

that he slumped because he was uncomfortable, and that although he

had grown up the part of Puerto Rico where the events at issue had

taken place, he had moved away from his hometown more than two

decades before, and rarely returned to visit. The court also asked

specifically if he recognized the name "Juan," and the juror

responded that he did not.


        14
       "I'm telling the truth, if in any case I would recognize
anybody of the persons involved in the case, it would come from me
to tell the Court . . . . I haven't."

                                       -29-
           Satisfied with the juror's credibility, the district

court continued the penalty phase of the trial.        Based on this

episode, Burgos filed a motion for acquittal or new trial and

requested an evidentiary hearing.      His motion also raised the new

argument that a defense witness from the guilt phase was also

related to the juror (her father was the juror's mother's cousin).15

The district court denied this motion on the grounds that the juror

was credible when he said he didn't recognize anyone in the

proceedings, and that moreover there hadn't been even a suggestion

that he had recognized the witness during the guilt phase.     Burgos

now appeals the denial of this motion.

           Burgos can hardly complain now that the district court

failed to remove the juror.   After all, the only jury finding made

after Burgos raised the issue favored Burgos by rejecting the death

penalty.   So he must train his argument on a claim that the

district court abused its discretion by failing to grant a new

trial because of later-discovered bias relevant to the guilt phase.

All Burgos has to go on is his belated complaint that a witness he

himself had called was a distant cousin of the juror.     Because the

district court took as credible the juror's statement that he did

not recognize anyone in the proceedings, Burgos instead makes an

argument based on implied bias:     that either the bare fact of a



     15
       In the motion, Burgos also raised a number of even more
attenuated connections.

                                -30-
blood relationship, or the fact that the juror lied about the

existence of a blood relationship, is sufficient to imply bias as

a matter of law.       See Amirault v. Fair, 968 F.2d 1404, 1406 (1st

Cir. 1992) (per curiam).

             Neither argument prevails.        First, the district court

concluded that the juror did not lie about not recognizing anyone

in the proceedings, and nothing suggests that finding was clearly

erroneous.     See id. at 1405 (stating that a court's findings of

juror credibility merit "great deference").           As for the bare fact

that the juror and the witness were distant cousins, implied bias

requires "exceptional" or "extreme" circumstances, id. at 1406

(quoting Smith v. Phillips, 455 U.S. 209, 222 (1982) (O'Connor, J.,

concurring)), and we cannot conclude that the district court erred

in finding the situation fell well short of this mark, given that

the familial connections were so attenuated that no one during the

guilt phase seems to have even noticed that the witness and the

juror were distant cousins.

             Burgos' alternative argument challenges the procedure

employed by the district court.         He says that the court erred by

investigating    the    claim   of   juror   bias   through   an   in   camera

discussion, rather than an evidentiary hearing.               The case law

suggests otherwise.      While a district court must make an "adequate

inquiry" into non-frivolous claims of juror bias or misconduct,

United States v. Ortiz-Arrigoitia, 996 F.2d 436, 442 (1st Cir.


                                     -31-
1993), the district court has "broad discretion to determine the

type of investigation which must be mounted."               United States v.

Boylan, 898 F.2d 230, 258 (1st Cir. 1990).            The court "may, but

need not, convene a full-blown evidentiary hearing."                  Id.   We

review the district court's determination of how to investigate

such claims for patent abuse of discretion.           Id.

          The district court certainly did not patently abuse that

broad discretion here.     The relevant question is not whether the

juror was actually related to anyone in the proceedings; it is

whether such a relationship, if it exists, biased the juror against

the defendant.    Indeed, the district court accepted that the juror

may have been related to the witness, but it credited the juror's

testimony that he did not recognize anyone, let alone harbor any

bias against the defendant as a result of that unrecognized

relationship with a witness for the defense.                 Thus, while an

evidentiary hearing could conceivably have proven the relationships

if they were at issue, they were not at issue.          The district court

did not patently abuse its discretion.

D.   Trial Before A Death-Qualified Jury

          Prior    to   trial,   Burgos   filed   a    number    of   motions

challenging the government's decision to seek the death penalty.

The district court denied them all.         Burgos was tried before a

death-qualified jury, and sentenced to life in prison.                 He now

argues that because he never should have faced the death penalty,


                                  -32-
his   trial    before     a   death-qualified    jury    violated      his   Sixth

Amendment rights.

              For his argument that he never should have faced the

death penalty in the first place, Burgos simply incorporates by

reference his pre-trial motions, offering no arguments for why the

district court erred in dismissing those motions.                      Arguments

incorporated into a brief solely by reference to district court

filings are deemed waived.           See Exec. Leasing Corp. v. Banco

Popular de P.R., 48 F.3d 66, 67-68 (1st Cir. 1995).                     As such,

Burgos has waived his argument that the district court erred when

it rejected his various motions to strike the death penalty.

              Given   a   proper   death     penalty    charge,   it    is    well

established that using a death-qualified jury for the guilt phase

does not violate a defendant's Sixth Amendment rights. Buchanan v.

Kentucky, 483 U.S. 402, 414-16 (1987).           Here, Burgos faced charges

of murdering Semidey to prevent her from, or in retaliation for,

communicating with law enforcement in violation of 18 U.S.C.

§§ 1512(a)(1)(A) and (C), and 1513(a)(1)(B), and the death penalty

is available for these violations as a matter of law.                          Id.

§§ 1111(b), 1512(a)(3)(A), 1513(a)(2)(A).              Thus, there has been no

Sixth Amendment violation.

E.    Sufficiency Of The Evidence

              Burgos next appeals from the order denying his motion for

acquittal or new trial on the basis of insufficient evidence to


                                      -33-
convict.   This court reviews a denial of a Rule 29 motion for

acquittal based on insufficiency of the evidence de novo, examining

the evidence in the light most favorable to the verdict,    United

States v. Troy, 583 F.3d 20, 24 (1st Cir. 2009), and asking whether

a rational jury could find guilt beyond a reasonable doubt, United

States v. Andujar, 49 F.3d 16, 20 (1st Cir. 1995).      A district

court's denial of a motion for a new trial is reviewed for manifest

abuse of discretion.   United States v. González-González, 136 F.3d

6, 12 (1st Cir. 1998).

           Burgos argues that the government presented insufficient

evidence that he killed Semidey with the intent to prevent her

attendance or testimony in an official proceeding, 18 U.S.C.

§ 1512(a)(1)(A), to "prevent a communication about the commission

or possible commission of a federal offense to a federal law

enforcement officer," id. § 1512(a)(1)(C), or to "retaliate" for

providing such information, id. § 1513(a)(1)(B).   As Burgos would

have it, the evidence at worst established two equally plausible

reasons for him to have killed Semidey:       he killed her in a

domestic dispute because they had an argument three days before her

disappearance that, according to trial testimony, did not seem to

have anything to do with her being an informant,16 or he killed her


     16
       Semidey's mother testified that the fight began when Burgos
said he wouldn't sell a kilogram of cocaine to a certain person and
Semidey said she would have sold the drugs.        Her mother then
responded affirmatively to defense counsel's characterizing the
fight as being about the fact that Burgos didn't like that Semidey

                                -34-
because of her informing.           Alternatively, he says that it was

equally plausible that another member of the conspiracy killed her.

             We    agree   with   the    district      court    that these other

theories were not equally plausible. The jury heard testimony that

Burgos tried several times to confirm whether or not Semidey was an

informant,    that    he   concluded     that    she   was,    and   that   he   had

threatened to kill her and "make her disappear from the face of the

earth" if he ever found out that she was cooperating with the

government.       The jury heard, too, evidence of Burgos' drug-related

activities and Semidey's knowledge of those activities, providing

him with ample motive to make sure she never testified against him.

If Burgos was merely unhappy with his non-marital relationship, he

had numerous options for ending that relationship.                     If he was

unhappy   because      Semidey    was    a     government      informant    clearly

possessed of knowledge sufficient to convict him, he had fewer

reliable options available to him other than murder, or so the jury

could reasonably have concluded.

F.   Prejudicial Variance

             Burgos then argues that the evidence presented at trial

regarding the duration of the drug conspiracy constituted a fatal




was "acting like a drug dealer." Agent Iglesias also testified
that Semidey told him that the fight had to do with Burgos'
reluctance to sell drugs to a certain person.

                                        -35-
variance from that charged in the indictment.17   Burgos was charged

with one count of conspiracy to possess cocaine with intent to

distribute, and one of conspiracy to import cocaine, both of which

were charged to have extended from 1998 to 2005.      Burgos argues

that because the only evidence of the conspiracy in the 1998-99

time frame came from Corales, who was in prison for six months

starting in 2001, and who also testified as a witness for the

government in an unrelated murder case, there could not have been

a continuous 1998-2005 conspiracy to import and distribute cocaine.

He argues that at best, the government has presented evidence of

two distinct conspiracies (a distribution conspiracy in 1998-99,

and a conspiracy to import and distribute in 2004-0518), creating

a fatal variance from the 1998-2005 conspiracy charged in the

indictment.

          To determine whether a variance exists, we "review the

record to determine whether the evidence and reasonable inferences

therefrom, taken as a whole and in the light most favorable to the

prosecution, would allow a rational jury to determine beyond a



     17
       Burgos preserved this objection below through a mistrial
motion that the district court denied in open court.
     18
       Burgos' view of the events could arguably be characterized
as three or four conspiracies:          separate importation and
distribution conspiracies in both 2004-05 and 1998-99, although as
we discuss below, he argues that there was no evidence of an
importation conspiracy in 1998-99. However, because his primary
complaint turns on two distinct periods of time, we follow his lead
in referring to only "two" conspiracies.

                               -36-
reasonable doubt that a single conspiracy existed."           United States

v. Mangual-Santiago, 562 F.3d 411, 421 (1st Cir. 2009) (internal

quotation marks omitted).       "Although conflicting inferences may

arise, so long as the evidence is adequate to permit a reasonable

trier of fact to have found a single conspiracy beyond a reasonable

doubt, the jury's finding will not be disturbed on appeal."              Id.

Even if we find a variance, it "does not warrant reversal unless it

is prejudicial."   United States v. Yelaun, 541 F.3d 415, 419 (1st

Cir. 2008).   We review de novo the question of whether a variance

was prejudicial.       United States v. Wihbey, 75 F.3d 761, 774 (1st

Cir. 1996).

           The record contains sufficient evidence to support the

jury's finding that Burgos participated in a conspiracy from 1998

to 2005.   Corales testified that he met Burgos in 1998.            At the

time, both had their own drug points and were involved in unrelated

drug activities, although they knew people in common.           After their

meeting, he and Burgos began selling each other kilogram-quantities

of cocaine.   Corales went to jail, but only for six months in 2001,

during which time the two remained in contact (for example, Burgos

provided the ice cream for an inmate party Corales organized), and

when   Corales   was    released,   Burgos   gave   him   a   job   in   his

construction company.        Sometime around 2003 or 2004, the two

developed the plan to import drugs from the Dominican Republic,

which only got as far as stealing a boat.           When the government


                                    -37-
asked whether the exchange of drugs between Corales and Burgos

lasted throughout their seven-year relationship (meaning 1998 to

2005), Corales answered in the affirmative.19

           The government presented no evidence that other people

were involved in the conspiracy with Corales and Burgos until they

began planning to import drugs sometime around 2003 or 2004.

Thus, there is no evidence of a 1998-2005 conspiracy unless Corales

remained a member for the entire time.      Burgos argues that the gap

in the government's evidence and the bare fact that Corales went to

prison means that the conspiracy ended in 1999 and re-started

several years later.        A six-month hiatus, however, does not

necessarily mean the conspiracy ended.           See United States v.

Alejandro-Montañez, 778 F.3d 352, 359-60 (1st Cir. 2015). Nor does

the   imprisonment   of   conspiracy   members   necessarily   require   a

finding of withdrawal or abandonment.       See Mangual-Santiago, 562

F.3d at 422-23.

           Burgos points to two additional points that could suggest

Corales withdrew from the conspiracy: the fact that he gave up his



      19
        The exchange followed a discussion in which Corales was
unable to estimate how many kilograms of cocaine had changed hands
between him and Burgos during their relationship. It consists of:
          Q: Well, is it fair to say that this relationship
     went on for close to seven years?
          A: Yes.
          Q:   And throughout that time period, were there
     exchanges of drugs, either from you to him or from him to
     you in kilo quantities of cocaine?
          A: Yes.

                                  -38-
own drug points; and the fact that in 1999 he agreed to testify for

the government in unrelated cases.           (Although defense counsel

pushed Corales to admit he was "working for" or an "informant" for

the government, Corales insisted that all he agreed to do was show

up in court and testify.)     On balance, though, while the evidence

could have allowed the jury to infer that Corales withdrew from the

conspiracy with Burgos and began a new conspiracy with Burgos out

of the blue around 2003, it is also sufficient to support an

inference that Corales never withdrew from the original conspiracy.

Thus, there is no variance.

G.   Evidentiary Rulings

           Finally, Burgos challenges a number of the district

court's   evidentiary    rulings,   both   individually    and   for   their

cumulative impact.       As a general matter, this circuit reviews

evidentiary rulings for abuse of discretion.              Baker v. Dalkon

Shield Claimants Trust, 156 F.3d 248, 251-52 (1st Cir. 1998).

However, if the evidentiary ruling rests on an interpretation of

law, we review it de novo, with subsidiary fact-finding reviewed

for clear error.   Id.

           Even if a district court errs, such error does not

require reversal if it was harmless--i.e., if it can be said that

"'the judgment was not substantially swayed by the error.'" United

States v. Meserve, 271 F.3d 314, 329 (1st Cir. 2001) (quoting

Kotteakos v. United States, 328 U.S. 750, 765 (1946)).                   The


                                    -39-
government generally bears the burden of persuasion on whether an

error was harmless, although an appellate court may also consider

sua sponte whether an error was harmless.         United States v. Rose,

104 F.3d 1408, 1414-15 (1st Cir. 1997) (holding that a court may

hold that an error was harmless even if the government does not

make that argument, because of the seemingly mandatory text of Fed.

R. Crim. P. 52(a) and the policy interest in conserving judicial

resources).

           For claims that an evidentiary ruling violated the Sixth

Amendment's Confrontation Clause, the error must be harmless beyond

a reasonable doubt.     United States v. Cameron, 699 F.3d 621, 652

(1st Cir. 2012).    Cumulative errors may merit a reversal if they

achieve a "critical mass" that "cast[s] a shadow upon the integrity

of the verdict."    United States     v. Sepulveda, 15 F.3d 1161, 1196

(1st Cir. 1993).

     1.    Semidey's Hearsay Statements

           Burgos argues that the district court erred in admitting

Semidey's statements under the "forfeiture by wrongdoing" exception

to the rule against hearsay.         Fed. R. Evid. 804(b)(6).           That

exception allows the admission of hearsay statements "against a

party that wrongfully caused--or acquiesced in wrongfully causing--

the declarant's unavailability as a witness, and did so intending

that result."     Id.   We review for clear error the question of

whether   the   government   has   demonstrated   that   Burgos   had    the


                                   -40-
requisite intent for this exception to apply.    See Baker, 156 F.3d

at 252; see also United States v. Scott, 284 F.3d 758, 762 (7th

Cir. 2002) (question of whether Rule 804(b)(6) applies turns on

fact-finding).    This circuit has not defined the standard of

evidence necessary to establish the requisite intent, although for

the closely analogous claim that a defendant has waived his Sixth

Amendment right to confront a potential witness by murdering that

witness, this circuit requires the government to prove waiver by a

preponderance of the evidence, see United States v. Houlihan, 92

F.3d 1271, 1280 (1st Cir. 1996), and the majority of circuits seem

to apply this standard to Rule 804(b)(6), see Davis v. Washington,

547 U.S. 813, 833 (2006).   We do the same here.

           Our finding that the evidence was sufficient to convict

Burgos of murdering Semidey to make sure she did not share further

her knowledge of his criminal activity readily disposes of this

evidentiary challenge.   The only wrinkle Burgos seeks to introduce

is a claim that, for purposes of Rule 804(b)(6), the prosecution

must prove that charges had been filed at the time he killed

Semidey.    This circuit has previously held that the analogous

exception to the Confrontation Clause applies to the murder of

witnesses in criminal investigations even before charges have been

brought.   Houlihan, 92 F.3d at 1280.   The reasoning of that case is

just as applicable here, as the rule that Burgos advocates would

simply create an incentive to "murder suspected [witnesses] sooner


                                -41-
rather than later."           Id.   Thus, the forfeiture-by-wrongdoing

exception is available for statements by a witness who was murdered

before charges were brought if it was "reasonably foreseeable that

the investigation [would] culminate in the bringing of charges."

Id.   Here, the district court did not clearly err in concluding

that Burgos intended to prevent Semidey from testifying at a trial

that, had she continued working with the government, was reasonably

foreseeable to occur.

              Burgos' attempt to rely on Giles v. California, 554 U.S.

353 (2008) is misplaced.            That case merely established that

Rule 804(b)(6) and the analogous Confrontation Clause provision do

not   apply    without   an   intent    to    prevent   testimony--i.e.,   the

exception is not available for statements by murder victims simply

because the defendant made them unavailable.              Giles, 554 U.S. at

367-77.    It did not announce a rule that the murder must actually

follow the filing of charges.

      2.      Hearsay References To Burgos Being Under Investigation

              At trial, Burgos pursued lines of attack that made

relevant whether law enforcement had a preexisting investigation of

or interest in Burgos prior to Semidey becoming an informant.                A

DEA supervisor therefore testified that he already knew Burgos as

a person of interest before Semidey came into his office.                  Two

other agents so agreed. None of the witnesses testified about what




                                       -42-
it was that caused the agents to initially become suspicious of

Burgos.

             Burgos   now   claims   that   all   of   this   was   somehow

inadmissable hearsay.       We think not.    Having placed at issue the

chronology of the investigation, Burgos can hardly complain that

the government put on direct witnesses who could say when they

started looking at Burgos.      The fact that such testimony may have

implied that other persons told the agents something that caused

them to focus on Burgos hardly causes their first-hand, relevant

testimony concerning the investigation's status to become hearsay.

None of them even related the substance of what unnamed others may

have said, let alone offered it for its truth.20        See Fed. R. Evid.

801(c)(2).

     3.      Daubert Challenge To Testimony Of Dog Handlers

             At trial, the government introduced the testimony of

several law enforcement officers that one of two so-called "cadaver

dogs" "alerted" when led by an area on Burgos' property where one

of the officers had identified a possible grave site approximately

six months before.     Because no human remains were discovered, the

sole purpose of this testimony was to suggest that, because the dog

alerted, the jury could conclude that the location had, at one

point, concealed a human cadaver.


     20
        Semidey's husband's testimony that he had heard of the
investigation from the supervisor, even if it was hearsay, was
harmless because it was cumulative of the admissible testimony.

                                     -43-
          Burgos objected to this testimony on several grounds, in

particular that the testimony constituted, under Federal Rule of

Evidence 702, an expert opinion that the cadaver dog could reliably

locate a spot in which human remains had been buried, and that the

government had failed to lay a proper basis for its reliability

under Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579

(1993). The district court nevertheless allowed the testimony, and

Burgos now challenges that ruling on appeal.

          Upon reviewing the record, we tend to agree with Burgos

that the government did not lay out much of a case that a dog could

reliably identify a spot in which there had been (presumably months

earlier) a human cadaver, as opposed to simply responding to animal

remains or to the leash-holding handler's conscious or unconscious

cues.   It is one thing to use a dog to identify a place in which

one might look to see if human remains are present.    It is quite

another to use a dog to identify dirt that was once exposed to a

human cadaver.   The prosecution witnesses offered virtually no

evidence that the scientific reliability of such a use had been

established, or that their investigation protocols were generally

accepted for such a use.   Burgos' experts, in turn, provided easy-

to-follow testimony explaining numerous basic defects in the use of

the dogs for the purpose for which they were used here.   They also

offered much common sense, noting, for example, that the officer




                                -44-
using the dog on a leash that alerted was the officer who had

previously identified the suspected spot.

          Ultimately, however, we need not determine whether the

admission of the testimony was an abuse of discretion because it is

plain that, for two reasons, any possible error was harmless.

First, the government presented a large amount of much more

compelling circumstantial evidence that Burgos was responsible for

Semidey's death.   That evidence included testimony from Semidey's

brother-in-law that Burgos had repeatedly tried to confirm, and

then said he had confirmed, a rumor that Semidey was an informant;

testimony from Semidey's handlers that Semidey told them that

Burgos had threatened to make her disappear if he found out she was

working for the government; testimony from another witness that

Burgos had threatened to kill that witness if he told anyone that

Burgos knew that Semidey was an informant; testimony by Corales

that after Burgos learned that Semidey was an informant, Burgos had

asked Corales for a gun and said that Semidey was going to

disappear; and testimony that Semidey was last seen in Burgos' car.

The jury heard the recorded conversation between Corales and Burgos

in which Burgos said that Semidey would not be found.    They also

heard testimony that Burgos had choked Semidey during a fight,

which--even if the fight did not have to do with Semidey being an

informant--demonstrated (assuming the jury found it credible) that




                               -45-
Burgos was capable of violence.            Finally, trace DNA evidence was

found in the trunk of Burgos' car.

            It is no doubt true that Burgos offered evidence to the

contrary.    Among other things, Burgos pointed out a number of

inconsistencies in the testimony of the DEA agents investigating

him; established that Corales' credibility is, to put it mildly,

questionable; and offered evidence that the suspicious car-washing

and the DNA evidence recovered from the trunk may have had innocent

explanations.      On balance, though, we conclude that the evidence

other than the dog alert, while circumstantial, pointed quite

forcefully at Burgos.

            Our    second   reason   for    this   conclusion    is   that   the

testimony about the dog alert carried very little incremental

probative force because its limitations would be almost certainly

apparent to any reasonable jury.            Even though the dog handlers'

testimony    was    "scientific,     technical,     or   other    specialized

knowledge," see Fed. R. Evid. 702, it was at the non-technical end

of the spectrum.      Indeed, the prosecution did not even propose it

as expert testimony, and the witnesses offered no technical or

jargon-laden support for their claims.             The defense exposed the

limitations in the handlers' claims through easy-to-follow cross-

examination and persuasive testimony from an expert clearly more

knowledgeable on the matter than the officers.                  We expect the

jurors were well able to understand and evaluate these types of


                                     -46-
arguments that a dog may not be able to distinguish soil that once

contained a decomposed human from soil that once contained a

decomposed animal, or that a handler walking the dog on a leash

might cause the dog to alert.     In short, the testimony about the

alert of a cadaver dog that found no cadaver added little to the

case.

             This is not to say that the district court does not have

a responsibility to exercise its gatekeeper role under Rule 702

with regard to such testimony.    Indeed, in other contexts in which

the government seeks to offer dog alerts as substantive evidence

(for example, of the presence of an accelerant in an arson case),

courts routinely test the reliability of such testimony under

Daubert. See, e.g., United States v. Marji, 158 F.3d 60, 62-63 (2d

Cir. 1998) (per curiam).      It is, rather, to say that failure to

conduct such an analysis, assuming it is error, is more likely to

be harmless in a case such as this, in which the prosecution

witnesses cited no studies or reports to buttress their experience-

based observations, nor claimed any special scientific expertise,

and in which the defense gave the jury ample evidence from which to

judge for themselves whether a cadaver dog alert that revealed no

cadaver was anything more than a false alert.

        4.   Prior Bad Acts

             At trial, the government introduced as evidence a number

of recordings that Semidey had made of conversations with Burgos.


                                 -47-
One of those recordings reveals Burgos' involvement with drug

trafficking in a time frame that supports the prosecution's claim

that Burgos had been involved in such activity for a long time.           A

portion of that recording also includes a statement that, as part

of that drug trafficking conspiracy, he had served as a lookout for

a murder.

            Burgos objected to the evidence on two grounds: (1) that

the government failed to comply with Fed. R. Evid. 404(b)(2), which

requires that, upon request, the government must give notice of the

evidence of prior bad acts that it seeks to offer; and (2) that the

evidence was in any event inadmissible as propensity evidence

prohibited by Fed. R. Evid. 404(b). The district court allowed the

recording to be played, but also instructed the jury that the

statements about the murder may be false and should be ignored.21

            We begin with the notice issue.         The wrinkle in Burgos'

argument is that the government had provided the recordings to

defense several years before trial.           What it did not do was

specifically   call   attention   to   the   fact    that   they   contained

Rule 404(b) material, even though the defense sent an e-mail


     21
       The district court instructed the jury as follows: "These
statements by Mr. Burgos are uncorroborated and, as I mentioned to
you before lunch, for all we know he may have been huffing and
puffing to impress his girlfriend. Okay? You must not consider
the statements regarding those incidents for the truth of those
events. In other words, you must not take those things as proof
that the events actually occurred or that Mr. Burgos was in any way
involved in them, neither may you hold them against Mr. Burgos in
any other manner."

                                  -48-
specifically requesting such information.    We do not reject the

distinct possibility that a large bulk production may well be,

without more, deficient notice.       However, we need not decide

whether it is so here, because even if the notice was deficient,

the error was harmless.

          Burgos makes no argument at all that the lack of clear

notice caused him any prejudice at all.   Indeed, he does not even

argue that his counsel did not know beforehand that the government

would seek to play the recordings. We also have not identified for

ourselves any way that the defense strategy was hampered by lack of

specific notice, and therefore conclude that the lack of specific

notice was harmless.22

          That leaves the question of whether the evidence was

admissible on its merits.   On that question, Burgos argues both

that the district court erred in determining the evidence to be

admissible as offered for something other than propensity, and that

the admission of the evidence was not harmless. On the question of

admissibility, our review is for abuse of discretion.       United

States v. Rivera-Rivera, 477 F.3d 17, 20 (1st Cir. 2007).



     22
        Burgos offers two cases that he argues stand for the
proposition that the failure to provide notice of Rule 404(b)
evidence cannot be harmless. Both involve surprise testimony that
hampered the defense strategy in identifiable ways. United States
v. Carrasco, 381 F.3d 1237, 1240-41 (11th Cir. 2004) (undermining
a defense based on a lack of intent); United States v. Vega, 188
F.3d 1150, 1155 (9th Cir. 1999) (surprise witness prevented defense
from preparing for cross-examination on the prior acts).

                               -49-
           We   cannot   find   that    the    district   court   abused   its

discretion in allowing the recording as evidence relevant to an

issue other than propensity.      Although the government offered the

recording for purposes of dating the conspiracy, the district court

also stated that it was admissible as evidence of "motive" or

"opportunity." The recording confirms in Burgos' own voice that he

told Semidey things to which he would certainly not want her to

testify.   That fact was relevant to his motive to kill her.            And it

also corroborated her general claim that he confided in her in that

matter.    To the extent that the evidence might nevertheless have

been excluded as unfairly prejudicial under Rule 403, given that

the government had presented other evidence of Burgos' motive, the

trial court's limiting instruction to the jury tilted the balance

enough to trigger our deference to such a balancing.

     5.    Cell Phone Records

           Semidey   owned      and     used     a   cell    phone.        Her

telecommunications carrier was a company named Centennial, which

has since been acquired by AT&T Puerto Rico. In the regular course

of its business, Centennial maintained in its computer files data

for each call made by each user, including Semidey.                   The data

included the phone numbers dialed on Semidey's phone or from which

it received calls; the dates, times, and durations of the calls;

whether each call was incoming or outgoing; and the particular cell

tower that connected the phone to the network during the call.


                                      -50-
            During trial, the government introduced as an exhibit a

print-out    of       Centennial's   data      concerning   Semidey's   phone's

activity on various dates. The government also introduced a record

maintained by Centennial showing the locations of its cell towers,

including those cell towers to which its records show Semidey's

phone connected on the pertinent dates.             Centennial's records were

accompanied by a certification of the custody of Centennial's

records in compliance with Fed. R. Evid. 803(6)(D) and 902(11).

The government also presented testimony from a Centennial employee

describing Centennial's record-keeping practices and explaining the

data in the actual exhibits.            The employee who testified was not

the same employee who had queried Centennial's database to compile

the print-out used at trial.

            Burgos raised below (in connection with a motion in

limine and a voir dire examination of the Centennial witness) and

now presses on appeal three objections to the cell phone records.

            First, Burgos contends that because the print-out of

Semidey's phone records "was a highly specific document prepared

pursuant    to    a    request   from   law    enforcement,   containing   only

information requested by the agency," it did not qualify as an

exception to the hearsay rule under Fed. R. Evid. 803(6)(B) and

(D).   That exception applies to documents "kept in the course of a

regularly conducted activity of a business," and for which "making

the record was a regular practice of that activity."              Id.    Burgos


                                        -51-
devotes one sentence to this contention in a 127-page brief and

cites no precedent.

            Burgos' complaint about the Centennial exhibits could

apply to virtually any print-out of data stored in computerized

business records.    This circuit has previously held that exhibits

showing selected data pulled from records that a company keeps in

the ordinary course of business fall under the business records

exception, even if the physical exhibits themselves were made to

comply with a request from law enforcement.       United States v.

Cameron, 699 F.3d 621, 641-42 (1st Cir. 2012) (holding that

exhibits showing internet providers' records of when the defendant

logged in and out of his account and the IP address from which he

had logged in fell into the business records exception even though

the exhibits themselves were created in response to a search

warrant).    Other circuits have directly held that phone records

fall into the business records exception. See, e.g., United States

v. Yeley-Davis, 632 F.3d 673, 678-79 (10th Cir. 2011);       United

States v. Green, 396 F. App'x. 573, 575 (11th Cir. 2010) (per

curiam).    We see no reason to disagree here.

            Burgos argues, second, that the admission of the records

"failed the Confrontation Clause standard set in Melendez-Diaz v.

Massachusetts, 557 U.S. 305, 325 (2009)."    Why this is so, Burgos

does not explain.      Melendez-Diaz held that business records,

although not usually testimonial for purposes of triggering the


                                -52-
Confrontation Clause, may be testimonial if the regularly conducted

business activity is the creation of evidence for trial, such as

analyzing substances at a forensic lab.      See id. at 321-24.   In

this case, however, the exhibits contained no data or analysis

created for trial.    Rather, they were simply print-outs of data

created and stored by Centennial in the course of running a phone

company.

           Again, Cameron is instructive.    There, even though the

court concluded that records the company made in the regular course

of providing internet service were not testimonial for purposes of

triggering the Confrontation Clause, it held that records of the

company's reports to a child pornography tip line were.           It

reasoned that even though company employees made such reports as

part of the regular course of business, the purpose of reviewing

and reporting suspected child pornography was to facilitate law

enforcement.23   Id. at 647-48.    "[T]o create each Report, someone

at Yahoo! analyzed Yahoo!'s data, drew conclusions from that data,

and then made an entirely new statement [the tip line Report]

reflecting those conclusions. . . . This means that someone at

Yahoo! analyzed Yahoo!'s business records and concluded that (1) a

crime had likely been committed and (2) a particular user likely

committed that crime."   Id.


     23
       Because the records triggered the Confrontation Clause, the
court did not analyze whether they satisfied the business records
exception.

                                  -53-
            Here, Centennial responded to a request for data that it

had   previously    gathered    and   maintained   for   its   own   business

purposes.     The fact that the print-out of this data in this

particular format was requested for the litigation does not turn

the data contained in the print-out into information created for

litigation.      Rather, the physical manner in which the exhibit was

generated simply reflects the fact that the business records were

electronic, and hence their production required some choice and

offered   some    flexibility   in    printing   out   only    the   requested

information. See, e.g., Yeley-Davis, 632 F.3d at 678-79.

            Third, Burgos challenges a statement by the Centennial

witness that Semidey's phone was "in or around" the cell tower

listed as connecting the phone during a call. She then expanded on

this statement by responding in the affirmative when the government

asked whether the cell tower that connected the call "was closest

to the cell phone being used" when the call was initiated.             Burgos

argues that the witness was not qualified under Fed. R. Evid. 702

to offer testimony on the technical matter of how cell phone calls

are routed through a company's towers.             It does seem that the

witness's responses exceeded her knowledge--nothing on the exhibit

indicated that the connecting cell tower was always the closest

cell tower, and the witness explained on voir dire that she did not

have the knowledge or expertise to opine that the connecting cell

tower was actually closer than any other cell tower.


                                      -54-
          However, we conclude that the witness's gloss was of no

apparent material affect.    The prosecution used the evidence to

argue that Semidey must not have had her phone on July 2, shortly

before she disappeared: testimony established that at around eight

o'clock in the morning she was in Guánica, but the connecting tower

for a call received at 7:50 a.m. was in Levittown, more than sixty

miles away on the other side of the island.       (This, in turn, lent

indirect support to testimony by Semidey's brother-in-law that

Burgos said that he had confirmed Semidey was an informant because

he had her phone, and had seen that she had used it to call the

DEA.) Whether or not a phone necessarily connects to the "closest"

tower, any juror could have easily concluded that a cell phone

would not be sixty miles away from its connecting tower.            The

custodian's assertion that the connecting tower is the one closest

to the phone was of no significance at all in that context.

          Moreover, it is not even clear who the records helped

most.    Burgos'   counsel   chose   to   avoid   cross-examining   the

Centennial witness in front of the jury, and then used the exhibits

in closing to make several exculpatory points, one of which

involved the location of the phone.       While this approach did not

waive Burgos' objection to the exhibits, it does support our

conclusion that the Centennial witness's opinion about which tower

a phone connects to did not do real damage to Burgos' defense, and

may even have helped it.


                                -55-
      6.     Bolstering DNA Evidence With Hearsay

             At trial, the government introduced DNA evidence that

traces of Semidey's blood were found in Burgos' car. Burgos raised

a   number   of   concerns   about   the    analyst's   methodology.   The

government was allowed to elicit testimony that the department

protocol was to have each analyst's work reviewed by a second

analyst, and if they disagreed, then a third analyst was called.

It also elicited testimony that a third analyst was not called in

this case.    Burgos argues that this constitutes de facto testimony

by the second analyst that he was in agreement with the first.

Burgos argues that this violates the Confrontation Clause under

Melendez-Diaz, 557 U.S. at 310-11, because Burgos was unable to

cross-examine the second analyst.

             Burgos points to no case prohibiting the introduction of

testimony that internal review protocols had been followed unless

the reviewer is available to testify.           We again have difficulty

identifying this non-statement as hearsay, and also note that such

a rule would create a disincentive to this sort of internal control

mechanisms in forensic investigations.            As such, we decline to

announce such a rule, and hold that if there was error, any error

was harmless beyond a reasonable doubt because Burgos had ample

opportunity to cross-examine the primary analyst.

              Because we have disposed of several issues on harmless

error grounds, we have also considered whether all such possible


                                     -56-
errors   cumulatively were harmless.   We find that they were, given

how tangential the challenged evidence in question was, as compared

to the strong body of plainly admissible evidence supporting the

verdict.

                          III. Conclusion

           For the reasons stated above, we affirm.




                               -57-
