213 F.3d 10 (1st Cir. 2000)
UNITED STATES, Appellee,v.JOSEPH A. CHARLES, a/k/a SHIZ, Defendant, Appellant.UNITED STATES, Appellee, v.ELIZABETH AHART, Defendant, Appellant.
Nos. 98-2046, 98-2180
United States Court of Appeals For the First Circuit
Heard December 9, 1999Decided May 24, 2000

[Copyrighted Material Omitted][Copyrighted Material Omitted]
Kevin Reddington for appellant Joseph A. Charles and Frances L. Robinson, by appointment of the Court, for appellant  Elizabeth Ahart, were on consolidated brief.
Thomas C. Frongillo, Assistant United States Attorney, with  whom Donald K. Stern, United States Attorney, Dickens Mathieu,  Assistant United States Attorney, and Geline W. Williams, Special  Assistant United States Attorney, Plymouth County District  Attorney's Office, were on brief, for appellee.
Before: Torruella, Chief Judge, Cyr, Senior Circuit Judge, and Stahl, Circuit Judge.
TORRUELLA, Chief Judge.


1
On April 24, 1997, a federal  grand jury returned a three-count indictment charging Joseph A.  Charles, Elizabeth Ahart, and Reynard Mason with violations of  various federal narcotics and firearms laws.  After unsuccessfully  litigating a motion to suppress all evidence arising out of a  wiretap authorized by a Massachusetts court, see United States v. Charles, No. 97-10107-PBS, 1998 WL 204696 (D. Mass. Jan. 13, 1998),  Ahart and Charles entered conditional pleas of guilty.  On July 17,  1998, after holding an evidentiary hearing to determine the nature  of the narcotics, the district court sentenced Ahart and Charles to  168 months of imprisonment.  This appeal followed.1


2
For the reasons stated below, we affirm.

BACKGROUND

3
The district court aptly summarized the facts in this  case.  See id. at 1-5.  We see no need to duplicate that effort. Accordingly, we reiterate the district court's findings of fact  largely verbatim.


4
I.  State Criminal Investigation and Proceedings

A.  An Overview

5
From 1992 through 1995, the Massachusetts State Police  conducted an investigation of individuals based in the City of  Brockton who were suspected of engaging in the distribution of  large quantities of crack cocaine.  On July 24, 1995, the police  initiated a state-court-authorized wiretap on the telephone located  at 21 Field Street, a single family home in Brockton where  defendants Charles and Mason were residing.  A week-long wiretap  investigation yielded over 800 interceptions, the majority of which  pertained to the purchase and distribution of crack cocaine.  As a  result of information gleaned from the wiretap, state police  executed consecutive search warrants at 21 Field Street and 26  Allen Street, the Brockton apartment of defendant Ahart.  From the  latter search, the police seized approximately 221 grams of cocaine  base, drug paraphernalia, an Uzi rifle, ammunition, and $1,576 in  U.S. currency.  In August of 1995, a state grand jury indicted  Charles, Ahart, and Mason on various state drug and firearm  offenses.

B.  Wiretap Warrant and Order

6
On July 18, 1995, the Plymouth County District Attorney's  Office secured authorization from an associate justice of the  Superior Court (Cowin, J.) to intercept communications into and out  of 21 Field Street.  The application for the wiretap warrant was  submitted with a fifty-page affidavit of State Trooper Anthony  Thomas, which formed the basis of the court's probable cause  determination that narcotics transactions were being conducted by  way of the telephone line into the home.


7
In addition to the named targets of the investigation,  the application sought permission to intercept the calls of  defendant Charles's attorney, John W. Kelley, though nothing in the  accompanying affidavit suggested that Kelley was suspected of  criminal activity.  According to Trooper Thomas, he told Judge  Cowin that the application was unusual in that it sought to  intercept phone calls between Charles and Kelley in order to  determine whether the conversations were privileged.


8
The July 18 court order as initially drafted contained a  Minimization Notice which prohibited the interception of  "privileged communications."  In accordance with the wiretap  application, however, it also provided that if any conversations  with John W. Kelley of Brockton were intercepted, the police could  listen for 30 seconds to determine whether the contents were  privileged; if the wiretap monitor on duty determined that the  communications were not privileged, the interception would be  allowed to continue "an additional 30 seconds, unless and until the  conversations become privileged," at which time the monitoring  would cease.


9
On July 21, three days after issuing the order, the state  judge sua sponte amended her order.  The "Amended Minimization  Notice" eliminated the 30-second window that allowed the police  lead time to determine whether the content of a phone call was  privileged and specifically prohibited the interception of  communications with Attorney Kelley.  The order read as follows:


10
The officers executing this warrant shall not  intercept any conversations between persons at  the target telephone and incoming callers whom  the officers know, or have reason to believe,  have an attorney-client relationship with the  person to whom they are speaking.  This order  shall include any telephone conversations  between Attorney John W. Kelley of Brockton  and Joseph A. Charles, if the intercepting  officers know or have reason to believe the  speaker is the said Attorney Kelley.  There  shall be no interception of outgoing telephone  calls to . . . the office number of Attorney  John W. Kelley . . . .


11
The amended order contained no information regarding Kelley's  residential telephone.

C.  Intercepted Phone Calls

12
The wiretap ran from July 24, 1995 to July 30, 1995.  At  issue in this appeal are the events of July 29.  Trooper Paul  Petrino was the sole officer on monitoring duty in the State Police  Middleboro barracks from midnight on Friday, July 29 until 8 A.M.  the following morning.  Petrino had experience in monitoring  wiretaps and in narcotics investigations generally, but had not  played any part in the Charles investigation prior to July 28,  1995.2  Instead, he had been assigned to a highly publicized and  intense investigation involving the murder of a state trooper.


13
As required of all monitoring officers, Petrino signed  the minimization order on July 25, 1995, when he was first assigned  monitoring duties in this case.  He did not, however, re-sign or  review the order prior to July 28 or July 29, when he actually  began working on this case.  Prior to his monitoring assignment,  Petrino had never discussed the particulars of the Charles  investigation with Trooper Thomas, the officer in charge of the  wiretap; nor did he have any knowledge of any role Attorney Kelley  played in the investigation, including any suspicions harbored by  Thomas of Kelley's involvement.  Specifically, Petrino had no  knowledge that Kelley had been included in the original  minimization order and was later removed by amendment; and he had  no recollection of ever having met or spoken with Kelley.3


14
At the evidentiary hearing, Trooper Petrino explained the  process of how calls were monitored from the Middleboro listening  post in some detail.  For each call made to and from the 21 Field  Street telephone line, the monitoring equipment would display the  number that was dialed and begin recording.  Upon a determination  that a call was non-privileged, monitors would enter information  into a computer identifying the parties, nature, and substance of  each call in order to create a log of all interceptions.  Upon a  determination that a call was a privileged communication, monitors  were instructed to minimize the call by turning the tape off,  signified in the log by the notation "TTO" (Turn Tape Off).  In the  event that a series of calls were made in rapid succession, or when  the noise of the pen register made it difficult to hear the  conversations, monitors were instructed to jot down the gist of  each of the calls in handwritten notes and later play back the  tapes to make complete entries into the log.  Monitors were also  instructed to contact Trooper Thomas directly upon intercepting any  incriminating phone calls.4  While two monitors were ordinarily  assigned to the listening post on any given shift throughout the  course of the wiretap, Petrino served as the lone monitor during  his eight-hour shift on July 29 because all other law enforcement  personnel were needed to execute the search warrant that was  anticipated for that night.


15
Within the first two hours of his shift, between 1:20 and  1:55 A.M., Petrino intercepted seven calls in quick succession;  these calls mainly involved Mason reassuring callers that Charles  would soon be returning home from a short trip to New York City. This period was followed by a fifty minute break without any  incoming or outgoing calls.  From approximately 2:46 A.M., upon  returning home from his trip, Charles made a series of six calls  within eight minutes.  During the first of this series, Petrino's  entries in the log reflect Charles reporting to an unidentified  male, "it was a good night got 6 keys," inquiring "how much to  bring," and instructing him to call his "boy" and have him bring  "12 g's."  This series of calls and the previous series had been in  such rapid succession that Petrino had to play back the tapes to  make his log entries.  Petrino immediately paged Thomas and  informed him of the incriminating interception.


16
At approximately 3:12 A.M., the police entry team  executed a search warrant at 21 Field Street.  Expecting to find  the cocaine referred to in the intercepted calls, the police found  no drugs at all, recovering only a handgun and $4,500 in cash from  a car registered to defendant Ahart.  Charles was not arrested and  the police left the premises just before 5:00 A.M.  Because it was  a dry run, Thomas told Petrino that the phones were likely to be  active.  The primary objective was to identify the location of the  narcotics.


17
Immediately following the search, from 4:59 to 5:05 A.M.,  Charles made a series of five phone calls relating the events that  had just taken place.  Petrino described this six minute monitoring  period as "extremely busy."  At 5:05 A.M., Charles dialed a number  that was neither listed in the amended minimization notice nor  known to Trooper Petrino.  When a man answered, Charles said,  "Hello, Mr. Kelley, I'm sorry for calling the house so late. This  is Joseph.  Yo, I got some problems, man."  Describing the police  search, he continued:


18
Mr. Tony Thomas and them just ran up in my  fucking house . . . [t]hey ain't found  nothing, though.  The only thing they found  was a firearm, but he didn't charge me with  that.  But he took my money out of the trunk  of my car.


19
The conversation lasted approximately four minutes. Charles and Kelley discussed the possibility of recovering the  seized money in court on Monday and suing the police, and the two  agreed to speak again after the weekend.  As the call was being  recorded, Petrino did not hear the words "Mr. Kelley" and did not  minimize the conversation.  Following standard procedure for the  interception of nonprivileged calls, Petrino initially jotted down  notes and later played back the tape several times to enter into  the computer the substance of the conversation and other pertinent  information.  "Mr. Kelley" was Charles' attorney, John W. Kelley,  so named in the minimization order.  The call was to Kelley's home  in Easton rather than his office in Brockton.


20
Upon completion of his shift at 8:00 A.M., Petrino went  home and went to bed.  According to his testimony before the  district court, he was oblivious to the fact that he had failed to  comply with the wiretap order.  Later that morning, Thomas returned  to the Middleboro barracks to check the log from Petrino's shift. Thomas testified that in reviewing Petrino's entries, he noticed  the 5:05 interception, and that Charles had spoken with "a male  named Kelley."  Thomas recognized that the number dialed was an  Easton number and knew that Attorney Kelley resided in Easton. Upon tracing the number and verifying that it was indeed the home  telephone line of Attorney Kelley, Thomas called Petrino at home to  inquire about the intercepted phone call.  While Petrino recalled  the interception, Petrino told Thomas he did not know that the  person he identified in his log as "a male named Kelley" was, in  fact, Charles' attorney, John Kelley.  Thomas believed it was a  good faith mistake.


21
Thomas immediately informed his supervisor, Sergeant  Nagle, of the interception.  Nagle was located at the listening  post at the time he received the call from Thomas, and responded to  the news by writing in large script across the chalkboard in the  monitoring room, "No Attorney Calls."  Thomas also notified his  commander, Lt. Bruce Gordon, who in turn notified the case  prosecutor on Sunday, July 30, after the wiretap and investigation  had been terminated.  Thomas's actions conformed with the Amended  Minimization Notice, which required that "[a]ny inadvertent  interception of a privileged communication must be reported  forthwith to the officer in charge, Trooper Anthony E. Thomas, Jr.,  and the supervising Assistant District Attorney, Geline W.  Williams."  The police did not inform the Superior Court of the  violation of the minimization order because they believed they were  not required to do so once the wiretap terminated.


22
That same day, subsequent to the interception of the  conversation between Charles and Kelley, the police intercepted two  incriminating conversations between Charles and Ahart at  approximately 9:24 A.M. and 9:55 A.M., which resulted in the  execution of the Allen Street search warrant and the subsequent  arrests of defendants Charles, Ahart, and Mason.  All subsequent,  post-arrest calls to Kelley and other counsel were properly  minimized.

II.  Federal Criminal Proceedings

23
A. Dismissal of the State Court Indictment & Initiation  of Federal Proceedings


24
The defendants were initially indicted by a Plymouth  County Grand Jury in August 1995 for narcotics-related offenses. On March 18, 1997, after a hearing,5 an associate justice of the  Superior Court (DelVecchio, J.) issued a memorandum and order  suppressing the entire wiretap and all physical evidence derived  therefrom based on Trooper Petrino's interception of the July 29,  1995 privileged Charles/Kelley phone call.  See Commonwealth v. Charles, Nos. 96995-96997, 96998-97000, slip op. at 13-14 (Plymouth  Super. Ct., Mar. 18, 1997).  The state court found that "the  government deliberately attempted to intercept a private  communication between Kelley and Charles in direct contravention of  the attorney-client privilege" and that "in light of this finding,  an across-the-board suppression of all evidence derived from the  wiretap is appropriate."  Id. at 13.  On March 19, 1997, the  Commonwealth filed a notice of appeal.


25
That same day, the Plymouth County District Attorney's  Office contacted the United States Attorney's Office to review the  case with the Federal Bureau of Investigation (FBI) for possible  federal prosecution.  The United States Attorney's Office decided  to file federal charges based upon the FBI's recommendation and the  following factors: (1) the large quantity of drugs allegedly  involved; (2) the dangerous nature of crack cocaine; (3) the large  number of unindicted members of the suspected drug organization, as  indicated by intercepted phone conversations; (4) the defendants'  alleged use of firearms, including an Uzi semi-automatic firearm  with an obliterated serial number; (5) the criminal records of  defendants Ahart and Mason; (6) defendant Mason's apparent  propensity for violence; (7) evidence that the drug conspiracy  dated back to at least 1992; (8) the broad scope of the enterprise,  including evidence of a drug supplier in New York City and  confederates in Boston and Brockton; (9) the likelihood that  defendants would continue to engage in drug trafficking if  acquitted on state charges; and (10) the significant problems that  Brockton had suffered in recent years due to narcotics trafficking  and related violence.  John Woudenberg, a Special Agent with the  FBI, said that the possibility of a New York supply connection for  the crack was particularly significant.


26
On March 21, 1997, a federal magistrate issued complaints  charging defendants Charles, Mason, and Ahart with conspiracy to  distribute cocaine base in violation of 21 U.S.C. § 846 (Count 1);  charging Charles and Ahart with possession of cocaine base with  intent to distribute in violation of 21 U.S.C. § 841(a)(1) (Count  2); and charging Ahart with being a felon in possession of a  firearm in violation of 18 U.S.C. § 922(g)(1) (Count 3).  A grand  jury indictment followed on April 24, 1997.  The Commonwealth  terminated its prosecution by filing a Notice of Nolle Prosequi.


27
B. Appellants' Motions for Suppression of the Evidence  and Dismissal of the Indictment


28
Proceeding before the federal district court, Charles and  Ahart filed motions to dismiss the indictment based on the  doctrines of abstention, collateral estoppel, and prosecutorial  vindictiveness; to suppress the wiretapped conversations and all  evidence derived therefrom, pursuant to federal and state wiretap  law and the Fourth Amendment to the United States Constitution; and  to suppress all physical evidence, on the ground that the relevant  search warrants were invalid.  After a three-day evidentiary  hearing held on September 2, 4, and 8, 1997, the district court  granted defendants' motion to suppress the Charles-Kelley phone  conversation on grounds that it was protected by the  attorney-client privilege and subject to a minimization order, but  denied the motion to suppress with respect to all other evidence  derived from the wiretapped conversations.  See Charles, 1998 WL  204696, at *22.  As a corollary to this ruling, the court denied  the motion to dismiss.  See id.


29
In reaching this determination, the district court  specifically found that Petrino's interception of the  Charles-Kelley phone call was inadvertent and unintentional, albeit  negligent.  See id. at 4.  The court also found that overall the  state law enforcement officials managed the implementation of the  minimization order in good faith and in an objectively reasonable  manner.  See id.

DISCUSSION
I.  Standard of Review

30
In this Circuit, appellate review of a suppression motion  is bifurcated.  "In reviewing a denial of a suppression motion, the  district court's ultimate legal conclusion, including the  determination that a given set of facts constituted probable cause,  is a question of law subject to de novo review."  E.g., United  States v. Khounsavanh, 113 F.3d 279, 282 (1st Cir. 1997).  The  trial court's findings of facts, in contrast, must be upheld unless  they are clearly erroneous.  See, e.g., id.; United States v. Young, 105 F.3d 1, 5 (1st Cir. 1997).  "A clear error exists only  if, after considering all of the evidence, we are left with a  definite and firm conviction that a mistake has been made."  United  States v. McCarthy, 77 F.3d 522, 529 (1st Cir. 1996).  This  deference to the district court's findings of facts "reflects our  awareness that the trial judge, who hears the testimony, observes  the witnesses' demeanor and evaluates the facts first hand, sits in  the best position to determine what actually happened."  Young, 105  F.3d at 5.  As a corollary, "we will uphold a district court's  decision to deny a suppression motion provided that any reasonable  view of the evidence supports the decision."  McCarthy, 77 F.3d at  529.

II.  Motion to Suppress the Wiretap Evidence

31
Appellants raise two arguments in support of their motion  to suppress the wiretapped conversations and the evidence arising  therefrom:  (1) the evidence gleaned from the wiretap of the 21  Field Street phone line is not admissible pursuant to the Federal  Wiretap Statute, 18 U.S.C. §§ 2510 et seq., and (2) the state  court's suppression ruling collaterally estops the government from  using the wiretap evidence.  Neither argument prevails.  Instead,  we hold that the district court's limited suppression of the  Charles/Kelley phone call was an appropriate remedy for the state  police's violation of the amended minimization order.

A.  18 U.S.C. § 2516(2)

32
In support of their argument for suppression appellants  cite 18 U.S.C. § 2516(2), which provides authority for receipt in  federal court of state authorized wiretaps.  The statute provides,  in relevant part:


33
The principal prosecuting attorney of any  State, or the principal prosecuting attorney  of any political subdivision thereof, if such  attorney is authorized by a statute of that  State to make application to a State court  judge of competent jurisdiction for an order  authorizing or approving the interception of  wire, oral, or electronic communications, may  apply to such judge for, and such judge may  grant in conformity with section 2518 of this  chapter and with the applicable State statute  an order authorizing, or approving the  interception of wire, oral, or electronic  communications by investigative or law  enforcement officers having responsibility for  the investigation of the offense as to which  the application is made . . . .


34
18 U.S.C. § 2516(2).  According to appellants, § 2516(2) requires  federal courts to defer to state law in circumstances where, as  here, the federal prosecution attempts to make use of wiretap  evidence obtained through use of a state court warrant.  If state  law applies, appellants reason, thedistrict court was required to  suppress the evidence arising out of the 21 Field Street wiretap  because the state court had done so in the prior state proceeding. Appellants misconstrue the statute.


35
The district court correctly ruled that federal law  governs the admissibility of evidence in federal prosecutions. See, e.g., United States v. Wilson, 36 F.3d 205, 208 (1st Cir.  1994); United States v. Mitro, 880 F.2d 1480, 1485 n.7 (1st Cir.  1989).  As a result, "[e]vidence obtained in violation of neither  the Constitution nor federal law is admissible in federal court  proceedings without regard to state law."  United States v. Sutherland, 929 F.2d 765, 769 (1st Cir. 1991) (quoting United  States v. Little, 753 F.2d 1420, 1434 (9th Cir. 1984)).  This is  true even when the evidence "is obtained pursuant to a state search  warrant or in the course of a state investigation."  Mitro, 880  F.2d at 1485 n.7.  Considering a question closely related to the  one we face today, the Supreme Court has squarely affirmed this  principle:


36
In determining whether there has been an  unreasonable search and seizure by state  officers, a federal court must make an  independent inquiry, whether or not there has  been such an inquiry by a state court, and  irrespective of how any such inquiry may have  turned out.  The test is one of federal law,  neither enlarged by what one state court may  have countenanced, nor diminished by what  another may have colorably suppressed.


37
Elkins v. United States, 364 U.S. 206, 223-24 (1960).


38
Against this background, we turn to three decisions that  are directly on point and foreclose appellants' argument.  In United States v. Miller, 116 F.3d 641, 662-64 (2d Cir. 1997), the  defendants relied on a prior state court suppression order to argue  that the district court improperly denied their motion to suppress  all evidence gleaned from a state-court-authorized wiretap.  The  Second Circuit rejected the argument, stating:


39
[T]he state court's suppression order did not  foreclose consideration of the wiretap  evidence by the grand jury, and it was not  binding on the district court.  The latter  court properly held an evidentiary hearing on  defendants' suppression motion and considered  the motion on its merits.


40
Id. at 663.  The Miller Court reasoned that "'state court rulings  in a criminal trial are not binding on a federal court'" because  "'state and national sovereignty are separate and distinct from one  another.'"  Id. (quoting United States v. Miller, 14 F.3d 761, 763  (2d Cir. 1994)).


41
An identical result was reached in United States v. Williams, 124 F.3d 411, 426-28 (3d Cir. 1997).  In Williams, the  Third Circuit rejected the argument that § 2516(2) required the  district court to suppress state wiretap evidence where  communications intercepted pursuant to a state statute were  subsequently disclosed to federal authorities in violation of state  law.  See id. at 426.  Instead, the court applied federal law and  held that it did not require suppression.  See id. at 427-28.


42
Finally, in United States v. Padilla-Pena, 129 F.3d 457,  464 (8th Cir. 1997), the defendants unsuccessfully argued that  state wiretap evidence was inadmissible in a federal trial because  the wiretap minimization procedures applied by the local police  violated state law.  The court concluded that the state officers  had complied with 18 U.S.C. § 2518(5) and emphasized that "evidence  obtained in violation of a state law is admissible in a federal  criminal trial if the evidence was obtained without violating the  Constitution or federal law."  Id.


43
Miller, Williams, and Padilla-Pena foreclose appellants'  argument that § 2516(2) requires a federal court to apply state law  in determining the admissibility of state wiretap evidence.  While  we need look no further, we find additional support for our  conclusion in United States v. Sutherland, 929 F.2d 765 (1st Cir.  1991), a decision that does not directly address the reach of  § 2516(2).


44
In Sutherland, state law enforcement personnel utilized  an informant to procure incriminating tape recordings without a  warrant.  See id. at 769.  Under Massachusetts law, warrantless  interception of oral and wire communications is prohibited absent  consent of all the parties, except in two circumstances which did  not apply to the case.  See Mass. Gen. Laws ch. 272, § 99.  The  Commonwealth conceded that the tape recordings had been obtained in  violation of state law and consequently that testimony derived  therefrom could not be used as substantive evidence in a  Massachusetts prosecution.  The Commonwealth, however, moved in  limine for a determination that it would be allowed to use the  tapes as impeachment evidence.  The question was presented to the  Supreme Judicial Court, which held that the recorded conversations  were not admissible for any purpose.  See Sutherland, 929 F.2d at  769 (citing Commonwealth v. Fini, 531 N.E.2d 570, 574 (Mass.  1988)).  As a result of this ruling, the Commonwealth dismissed the  case.


45
A federal indictment followed.  Prior to trial, the  defendants moved to suppress on the ground that the tape recordings  were obtained by state law enforcement personnel in violation of  the Massachusetts wiretap law.  The district court denied the  motion and this Court affirmed, stating "we hold that in federal  criminal prosecutions, the admissibility of wiretap evidence is a  question of federal law."  Id. at 771.  Today, we reaffirm the  holding of Sutherland and apply it with equal force to this case.


46
In so doing, we once again leave open the possibility  that "in an extreme case of flagrant abuse of the law by state  officials, where federal officials seek to capitalize on that  abuse, this court might choose to exercise its supervisory powers  by excluding ill-gotten evidence."  Id. at 770.  Here, however, the  district court found that "overall, the state law enforcement  officials managed the implementation of the minimization order in  good faith and in an objectively reasonable manner."  Charles, 1998  WL 204696, at *4.  This determination is not clearly erroneous; to  the contrary, it is amply supported by the record and therefore we  decline to overturn it.  See Khounsavanh, 113 F.3d at 282.


47
Finally, in rejecting appellants' § 2516(2) argument, we  recognize that several courts have concluded that § 2516(2) may  require the application of state law where the state wiretap  statute contains standards that are more protective of privacy than  the corresponding provisions of the Federal Wiretap Statute.  See, e.g., United States v. McNulty, 729 F.2d 1243, 1264 (10th Cir.  1983) (en banc); Unites States v. Marion, 535 F.2d 697, 702 (2d  Cir. 1976).  In Marion, for example, the court stated:


48
[W]hether the proceedings be federal or state,  interpretation of a state wiretap statute can  never be controlling where it might impose  requirements less stringent than the  controlling standard of Title III.  If a state  should set forth procedures more exacting than  those of the federal statute, however, the  validity of the interceptions and the orders  of authorization by which they were made would  have to comply with that test as well.


49
Marion, 535 F.2d at 702 (footnote omitted).  This rule of law,  however, is not applicable to this case.  As the district court  stated, "[b]ecause the state court's suppression order in this case  was not based upon the application of more stringent standards  governing authorization procedures for wiretap orders under  Massachusetts law, this line of cases is inapposite to defendants'  claim, which hinges on the appropriate remedy for violation of a  minimization order."  Charles, 1998 WL 204696, at *10 (footnote  omitted).


50
In other words, appellants' reliance on the Marion line  of cases is misplaced. The Massachusetts wiretap statute does not  contain a higher standard for assessing minimization violations. To the contrary, the state statute does not contain any express  minimization provisions.  Instead, Massachusetts courts consult federal law in ruling on violations of minimization orders.  See, e.g., Commonwealth v. Vitello, 327 N.E.2d 819, 842 n.22 (Mass.  1975); Commonwealth v. Wallace, 493 N.E.2d 216, 221 n.10 (Mass.  App. Ct. 1986).  This case is no exception:  the state court  expressly relied on federal case law in determining the appropriate  remedy for the violation of the minimization order.  SeeCommonwealth v. Charles, slip op. at 7 ("Since there appears to be  no Massachusetts case directly on point, this court must be guided  by federal law.").


51
As indicated, "in federal criminal prosecutions, the  admissibility of wiretap evidence is a question of federal law." Sutherland, 929 F.2d at 771.  It follows that § 2516(2) does not  require a federal court to defer to a state court's application of  federal standards for a violation of a minimization order.

B.  Collateral Estoppel

52
Appellants next allege that the state court suppression  ruling should collaterally estop the federal government from using  the wiretap evidence.  This argument was not presented to the  district court.  Instead, appellants took the position before the  lower court that collateral estoppel should bar the entire  prosecution.  Appellants apparently now recognize, as the district  correctly observed in its astute opinion, that even if collateral  estoppel applied, it nevertheless would not operate to require  dismissal of the indictment.  See Charles, 1998 WL 204696, at *6. Because appellants failed to present this argument to the district  court, it is waived.  See, e.g., United States v. Slade, 980 F.2d  27, 31 (1st Cir. 1992) ("[A] party is not at liberty to articulate  specific arguments for the first time on appeal simply because the  general issue was before the district court.").


53
Moreover, even if appellants' collateral estoppel  argument were properly before this Court, we see no merit in it. "In this circuit it is well established that a ruling in a state  prosecution will collaterally estop the federal government only if  federal authorities substantially controlled the state action or  were virtually represented by the state court prosecutor." Sutherland, 929 F.2d at 771; see also United States v. Land at 5  Bell Rock Road, Freetown, Mass., 896 F.2d 605, 610 (1st Cir. 1990); United States v. Bonilla Romero, 836 F.2d 39, 43 (1st Cir. 1987). The record in this case conclusively shows that the federal  government was not a party to any aspect of the state investigation  or the state court proceedings.  Appellants concede as much, but  point out that the state prosecutor, Assistant District Attorney  Geline W. Williams, was appointed Special Assistant United States  Attorney in order to assist in the subsequent federal prosecution. This argument has been considered and rejected by at least two  other circuits.  See United States v. Perchitti, 955 F.2d 674, 677  (11th Cir. 1992); United States v. Safari, 849 F.2d 891, 893 (4th  Cir. 1988).  We join these circuits in holding that the appointment  of a state prosecutor as a special federal prosecutor, subsequent  to the state court action, "does not retroactively make the federal  government a party to an earlier state court proceeding."  Safari,  849 F.2d at 893.  Consequently, appellants' collateral estoppel  argument fails.

C.  Limited Suppression

54
In the alternative, appellants argue that the district  court's remedy for the violation of the amended minimization order  was inadequate.  We reject this argument.


55
The district court ruled that the interception of the  July 29 Charles/Kelley phone call was in clear violation of the  amended minimization order, entitling appellant Charles to a  suppression remedy under § 2518(1)(a)(iii).  See Charles, 1998 WL  204696, at *12.  The district court, however, declined to  invalidate the entire wiretap.  Instead, the court ruled that the  appropriate remedy was the limited suppression of the  Charles/Kelley call because the totality of the circumstances  demonstrates that the state police's minimization efforts were  reasonably managed.  See id. at 13-14.  The district court's ruling  is amply supported by both the law and the record.


56
The Federal Wiretap Statute requires the government to  conduct electronic surveillance "in such a way as to minimize the  interception of communications not otherwise subject to  interception."  18 U.S.C. § 2518(5).  In Scott v. United States,  436 U.S. 128, 137-39 (1978), the Supreme Court adopted a standard  of "objective reasonableness" for assessing minimization  violations.  Under Scott, the critical inquiry is whether the  minimization effort was managed reasonably in light of the totality  of the circumstances.  See United States v. Hoffman, 832 F.2d 554,  557 (1st Cir. 1989); see also United States v. Uribe, 890 F.2d 554,  557 (1st Cir. 1989) ("The touchstone in assessing minimization is  the objective reasonableness of the interceptor's conduct.").  In  making this determination, we are mindful that the reasonableness  of the monitor's conduct must be viewed "in the context of the  entire wiretap as opposed to a chat-by-chat analysis."  Hoffman,  832 F.2d at 1308.  Equally important, "[t]he government is held to  a standard of honest effort; perfection is usually not attainable,  and is certainly not legally required."  Uribe, 890 F.2d at 557. Although compliance determinations are necessarily fact-specific,  three factors are often crucial in measuring the reasonableness of  the government's conduct: (1) the nature and complexity of the  suspected crimes, (2) the thoroughness of the government  precautions to bring about minimization, and (3) the degree of  judicial supervision over the surveillance practices.  See United  States v. London, 66 F.3d 1227, 1236 (1st Cir. 1995); Uribe, 890  F.2d at 557; United States v. Angiulo, 847 F.2d 956, 979 (1st Cir.  1988).  Finally, we note that where an investigation involves a  drug ring of unknown proportion, as in this case, "the need to  allow latitude to eavesdroppers is close to its zenith."  Hoffman,  832 F.2d at 1308.


57
Our opinion in Hoffman, which involved a minimization  violation far more significant than the one in this case, is  instructive.  In Hoffman, federal agents monitoring a wiretap in a  narcotics investigation intercepted 22 calls between a suspect's  wife and her attorney.  The defendants moved to suppress the entire  wiretap on the ground that the agents had flagrantly disregarded  both federal law, see 18 U.S.C. § 2518(5), and the district court's  minimization order.  The district court denied the motion, electing  instead to suppress only the offending calls.  This Court affirmed  on the basis that "[t]he minimization effort, assayed in light of  the totality of the circumstances, was managed reasonably." Hoffman, 832 F.2d at 1307-08.  In reaching this conclusion, the Hoffman Court rejected the "suggestion that total suppression must  be ordered to forestall future misconduct," but left open the  possibility that "in a particularly horrendous case, total  suppression may be . . . an 'appropriate' remedy."  Id. at 1309.


58
Here, the record is replete with evidence supporting the  district court's findings that the state police managed the wiretap  in an objectively reasonable manner, took due precautions not to  overreach, and minimized non-pertinent calls as soon as  practicable.  Accordingly, we pause only briefly to highlight some  of the more salient facts.


59
As in Hoffman, this was a lengthy and complex  investigation involving a significant number of drug traffickers  engaged in interstate narcotics activity.  During the seven days  that the wiretap was active, the state police intercepted over 800  telephone calls, most of which involved drug activity.They  minimized 62 calls, including four calls involving attorneys.  The  inadvertent interception of the July 29 Charles/Kelly call was the  only minimization error that occurred; notably, the monitors  correctly minimized all other calls involving attorneys.  In  addition, the state police terminated the wiretap after achieving  their objective and did not rely on any information gleaned from  the Charles/Kelley call during any aspect of the investigation. Equally important, judicial supervision over the wiretap was  pervasive.  First, the wiretap application was supported by a  detailed, fifty-page affidavit of Trooper Thomas.  Second, the  Superior Court carefully reviewed the application and issued an  amended minimization order three days after issuing the initial  order.  Third, the court order was limited to a single telephone  for a period of 15 days.


60
As indicated, given this record we see no error in the  district court's determination that "the electronic surveillance  was managed reasonably."  Charles, 1998 WL 204696, at *15 (internal  quotation marks and citation omitted).  Accordingly, "there was no  taint upon the investigation as a whole sufficient to warrant the  sweeping relief which [the appellants] urge[]."  Hoffman, 832 F.2d  at 1307.  To the contrary, the district court correctly limited  suppression to the July 29 Charles/Kelley phone call only.  See id.

III.  Abstention

61
In yet another iteration of their argument that the state  court decision should have precluded the government from using the  wiretap evidence, appellants invoke the abstention doctrine.  This  argument misses the mark, and we need not discuss it in depth.


62
There are several well-known doctrines of abstention. See Bath Mem'l Hosp. v. Maine Health Care Fin. Comm'n, 853 F.2d  1007, 1012-13 (1st Cir. 1988) (discussing the various abstention  doctrines); see also 17A Charles Alan Wright et al., Federal  Practice and Procedure § 4241 (1998) (same).  In this case,  however, appellants do not cite a specific theory of abstention. Instead, appellants quote the following passage in support of their  contention that the district court should have dismissed the  indictment:  "A federal court, by abstaining, may avoid having to  decide a uniquely difficult question of state law of great local  impact and uniquely important local concern."  Bath, 853 F.2d at  1012 (citing Louisiana Power & Light Co. v. Thibodaux, 360 U.S. 25  (1959)).  As we have already indicated, the district court properly  ruled that "federal law governs the admissibility of evidence in  federal proceedings, regardless of whether that evidence may have  been obtained in violation of state law."  Charles, 1998 WL 204696,  at *6 (citing Sutherland, 929 F.2d at 769).  Consequently, contrary  to appellants' assertion, the district court simply did not "decide  a uniquely difficult question of state law."  Bath, 853 F.2d at  1012.


63
Moreover, it is equally clear that none of the recognized  doctrines of abstention apply in this case.  First, Pullman abstention is inapplicable because this case did not involve a  federal constitutional issue that would be mooted or placed in a  different posture upon construction of a state law.  See Pullman  Comm'n of Texas v. Pullman Co., 312 U.S. 496, 501 (1941).  Second,  the Burford doctrine does not apply, as there is no complex state  regulatory scheme.  See Burford v. Sun Oil Co., 319 U.S. 315, 333-34 (1943).  Finally, because ongoing state court proceedings are a  necessary prerequisite to both Younger abstention and Colorado  River principles, these doctrines are likewise inapplicable.  SeeColorado River Water Conservation Dist. v. United States, 424 U.S.  800, 881 (1976); Younger v. Harris, 401 U.S. 37, 40 (1971).  In  short, appellants have failed to raise a colorable argument in  support of federal abstention.

IV.  Franks Violation

64
Appellants allege that the evidence seized at Allen  Street must be suppressed because the state police intentionally  omitted material information from the warrant affidavit in order to  mislead the magistrate judge.  Appellants cite Franks v. Delaware,  438 U.S. 154, 171-72 (1978), in support of this argument.


65
In Franks, the Supreme Court held that a defendant was  entitled to a hearing at which he could challenge the truthfulness  of statements made in an affidavit supporting a search warrant if  the defendant made a substantial showing that (1) a statement in  the affidavit was knowingly and intentionally false, or made with  reckless disregard for the truth, and (2) the falsehood was  necessary to the finding of probable cause.  See id.  In this  Circuit, material omissions by an affiant are sufficient to  constitute the basis for a Franks hearing.  See United States v. Parcels of Land, 903 F.2d 36, 46 (1st Cir. 1990); United States v. Rumney, 867 F.2d 714, 720 (1st Cir. 1989).  However, a district  court's determination that the requisite showing has not been made  will be overturned only if clearly erroneous.  See Parcels of Land,  903 F.2d at 46; Rumney, 867 F.2d at 720; United States v. Southard,  700 F.2d 1, 10 (1st Cir. 1983).


66
Here, appellants allege that Trooper Thomas's failure to  include information pertaining to the violation of the amended  minimization order was a material omission in the affidavit for the  Allen Street search warrant.  We disagree.  The district court  correctly ruled that interception of the Charles/Kelly telephone  call did not invalidate the entire wiretap and warranted only  suppression of that one call.  Further, Thomas did not include any  information from the Charles/Kelley call in the affidavit.  The  magistrate judge, therefore, did not rely on any evidence that was  obtained due to the state police's failure to comply with the  minimization order.  Consequently, we conclude that the omission  was immaterial to the validity of the search warrant.  This  conclusion is fatal to appellants' argument.


67
V.  The District Court's Ruling that the Narcotic Involved in this  Case Constitutes Crack Cocaine


68
Appellants argue that the cocaine base involved in this  case is not crack cocaine for the purposes of the sentencing  guidelines.  See U.S.S.G. § 2D1.1(c).  In support of this argument,  appellants cite the low purity of the cocaine and complain that the  government produced no evidence regarding the melting point or  water solubility of the seized narcotic.  In the First Circuit,  whether contraband is crack is a question of fact which, once  found, is reviewed only for clear error.  See United States v. Robinson, 144 F.3d 104, 109 (1st Cir. 1998).  We see no error in  this case.


69
First, appellants' allegations regarding water solubility  and melting point have been squarely rejected by this Circuit.  SeeUnited States v. Ferreras, 192 F.3d 5, 11 (1st Cir. 1999); United  States v. Martnez, 144 F.3d 189, 190 (1st Cir. 1998); Robinson,  144 F.3d at 109.  In Martnez, for example, we stated:


70
[O]nce the government laid a proper foundation  "by introducing a chemical analysis . . .  proving that, chemically, the contraband was  cocaine base," no further scientific evidence  was needed.  Instead, the government could  bridge the evidentiary gap between cocaine  base and crack cocaine by presenting lay  opinion evidence (or an opinion proffered by  an expert who possessed practical as opposed  to academic credentials) from "a reliable  witness who possesses specialized knowledge"  (gained, say, by experience in dealing with  crack or familiarity with its appearance and  texture).


71
144 F.3d at 190 (quoting Robinson, 144 F.3d at 108-09) (alteration  in original). In this case, the government produced competent  scientific evidence from two chemists to prove that the 221 grams  of contraband seized at the time of appellants' arrest was cocaine  base.  Once the government introduced this testimony, no additional  scientific evidence was needed.  From that point forward, competent  lay testimony, such as that of Trooper Thomas, remarking on the  substance's distinctive appearance and texture and identifying it  as crack, completed the necessary link in the evidentiary chain. See Ferreras, 192 F.3d at 11; Martnez, 144 F.3d at 190; Robinson,  144 F.3d at 109.


72
Appellants' drug purity argument is also contrary to well  established law.  In Chapman v. United States, 500 U.S. 453 (1991),  the Supreme Court held that unless otherwise specified, the purity  of a controlled substance is not a factor in sentencing under 21  U.S.C. § 841(b).  See id. at 459-68.  The Court explained: "Congress adopted a 'market-oriented' approach to punishing drug  trafficking, under which the total quantity of what is distributed,  rather than the amount of pure drug involved, is used to determine  the length of the sentence."  Id. at 461.  The Court further  explained:


73
Congress clearly intended the dilutant,  cutting agent, or carrier medium to be  included in the weight of [cocaine] for  sentencing purposes.  Inactive ingredients are  combined with pure heroin or cocaine, and the  mixture is then sold to consumers as a heavily  diluted form of the drug.  In some cases, the  concentration of the drug in the mixture is  very low. . . .


74
By measuring the quantity of the drugs  according to the "street weight" of the drugs  in the diluted form in which they are sold,  rather than according to the net weight of the  active component, the statute [21 U.S.C.  § 841] and the Sentencing Guidelines increase  the penalty for persons who possess large  quantities of drugs, regardless of their  purity.  That is a rational sentencing scheme.


75
Id. at 460, 465.  As the Chapman Court indicated, the Sentencing  Guidelines explicitly adopt this approach:


76
Unless otherwise specified, the weight of a  controlled substance set forth in the table  refers to the entire weight of any mixture or  substance containing a detectable amount of  the controlled substance.  If a mixture or  substance contains more than one controlled  substance, the weight of the entire mixture or  substance is assigned to the controlled  substance that results in the greater offense  level.


77
U.S.S.G. § 2D1.1(c) note A.  Consequently, we conclude that the  district court properly based appellants' sentence on the total  weight of the narcotic without regard to the purity of the cocaine  base.  See Chapman, 500 U.S. at 460-65; U.S.S.G. § 2D1.1(c); see  also United States v. Cartwright, 6 F.3d 294, 303 (5th Cir. 1993).

CONCLUSION

78
For the reasons stated above, we AFFIRM appellants'  convictions and the corresponding sentences imposed by the district  court.



Notes:


1
   Reynard Mason is not a party to this appeal.


2
   There is some confusion in the record regarding whether Petrino  served as a monitor on July 28 as well as July 29.  The  government's trial brief stated he was a monitor only once, on  July 29; however, both the duty log and testimony before the  district court indicated that Petrino served on July 28 as well.


3
   Kelley testified at the state suppression hearing that he had  "met" Petrino prior to the date of the hearing.  When pressed on  cross-examination, however, Kelley admitted to having no specific  memory of ever being introduced to Petrino or ever having directly  spoken to Petrino in any capacity.


4
   That a call was designated incriminating versus nonincriminating  would be reflected in the log by the notations "I" or "N."  Other  columns within the log reflect the time the call was dialed, the  number dialed, and whether the call was incoming or outgoing,  signified by the notations "I" or "O."


5
   The transcript of that hearing was submitted to the district  court and is part of the record in this case.


