          United States Court of Appeals
                      For the First Circuit



No. 17-1530

                     UNITED STATES OF AMERICA,

                             Appellee,

                                v.

 WILFREDO RODRÍGUEZ-ROSADO, a/k/a La Gorda, a/k/a Mogoyo, a/k/a
                       Pitin, a/k/a Mogo,

                       Defendant, Appellant.



          APPEAL FROM THE UNITED STATES DISTRICT COURT
                 FOR THE DISTRICT OF PUERTO RICO

         [Hon. Francisco A. Besosa, U.S. District Judge]



                              Before

                        Howard, Chief Judge,
              Torruella and Thompson, Circuit Judges.




     Vivianne M. Marrero, Assistant Federal Public Defender
Supervisor, Appeals Section, and Eric Alexander Vos, Federal
Public Defender, on brief, for appellant.
     Thomas F. Klumper, Assistant United States Attorney Senior
Appellate Counsel, Mariana E. Bauzá-Almonte, Assistant United
States Attorney Chief, Appellate Division, and Rosa Emilia
Rodríguez-Vélez, United States Attorney, on brief, for appellee.
November 28, 2018
            THOMPSON, Circuit Judge.

                          Conducting the Performance

            Like the conductor of a grand symphony orchestra who

sets tempos, cues ensemble members, and modulates sounds, Wilfredo

Rodríguez-Rosado         led   his    coworkers          at   American    Airlines    (and

others)    in    a    decade-long,         Puerto        Rico-based,     drug-smuggling

conspiracy.      Performing as Rodríguez's instruments of crime, the

band of dope peddlers each played different, though no less

necessary, roles.         Some jam-packed suitcases with cocaine; others

drove the cases to airports.                    Some weaseled the cocaine-stuffed

suitcases       aboard     airplanes;           others        tiptoed    them   out    for

distribution.        With drugs and cash zipping up and down the United

States,     Rodríguez      and       his    squad     of       oh-so-sneaky     smugglers

trafficked ultimately more than 9,000 kilograms of cocaine.

                               Breaking Up the Band

            But drug-smuggling isn't music to everyone's ears, least

of   all   law    enforcement.             In    early    2009,    after    seizing    six

suitcases, chockfull of cocaine, a combined federal and state

taskforce busted Rodríguez and his group.                       And later that year, a

grand jury charged them with various drug offenses.                        These crimes

carried serious time.            Eventually, Rodríguez owned up to the

wrongdoings; he pleaded guilty to participating in a conspiracy to

possess with intent to distribute between 15 to 50 kilograms of

cocaine.        See 21 U.S.C. §§ 841(a)(1), 841(b)(1)(A)(ii), 846.


                                            - 3 -
Because Rodríguez accepted some responsibility for the offense,

the government in turn recommended a sentence of 14 to 17.5 years

— a substantial sentence, yes — but a fraction of the time he

could've   served    otherwise.1      The    judge,   consistent     with   the

government's proposed sentence range, gave Rodríguez 15 years'

incarceration.

                     Auditioning for a Better Deal

           A few years later, Rodríguez got a shot at nabbing an

even lower sentence.         In 2014, the U.S. Sentencing Commission

adopted Amendment 782.2       See United States Sentencing Commission,

Guidelines Manual, App. C Supp., Amend. 782 (reduction), 788

(retroactivity)      (Nov.   2018).         That   change,   which    applies

retroactively, reduced by two levels the base offense level for

most drug offenses, including the crime to which Rodríguez pleaded

guilty.    See id.     Days after Amendment 782 took effect, little

wonder Rodríguez filed a motion seeking a reduced sentence.3




     1 According to the plea agreement, the mandatory-minimum for
Rodríguez's crime was "a term of imprisonment of at least ten (10)
years, but no more than life; and a term of supervised release of
at least five (5) years." In addition, the sentencing court also
could have imposed a fine up to, but no more than, $4,000,000.00.

     2 The U.S. Sentencing Commission is an agency that issues and
updates the federal sentencing guidelines. See 28 U.S.C. § 994.

     3As both parties observe, applying Amendment 782 to Rodríguez
would reduce his guideline sentence range from 168-210 months to
135-168 months. See USSG § 2D1.1(c)(4) (2016); see also Rodríguez
I, 854 F.3d at 123.


                                   - 4 -
             But Rodríguez was not alone.           Indeed, in the wake of

Amendment 782's ratification, thousands of prisoners nationwide,

jailed for drug crimes, suddenly became eligible for reduced

sentences.    See United States v. Rodríguez-Rosado ("Rodríguez I"),

854 F.3d 122, 123 (1st Cir. 2017)(noting that "Amendment 782, as

expected, generated thousands of sentence reduction motions").

That   the    possible   early   release       of   tens    of    thousands    of

incarcerated people would strain the criminal justice system was

not lost on the Sentencing Commission.              See USSG App. C, Amend.

788 at 80–82 (imposing a one-year delay on the filing of Amendment-

782 motions to "permit courts and probation offices to effectively

supervise the increased number of defendants," ensure released

offenders'    successful   reentry      to    society,   and     promote   public

safety).     Nor was it lost on the Puerto Rico federal court.                See

Rodríguez I, 854 F.3d at 123 (indicating that "the Puerto Rico

District Court" had to brainstorm how to "handl[e] the impending

onslaught of motions").        Indeed, just five days after Amendment

782's adoption, the Puerto Rico federal court devised a way to

keep pace with the motions — a formal, multi-step procedure called

Administrative Directive 14-426 ("AD 14-426").                 See In Re: USSG

Amend. 782, Misc. No. 14-426 (ADC)(D.P.R. Nov. 6, 2014).

             The   procedure   went    something     like   this:      After    a

defendant files a motion seeking a reduced sentence under Amendment

782, the clerk of the court automatically refers the case to a


                                      - 5 -
magistrate judge for "initial screening."             The magistrate judge is

tasked with figuring out whether the defendant is eligible for a

lower sentence, and nothing more.              Should the magistrate judge

find the defendant ineligible for less prison time, the motion

fails.4   But if the magistrate judge finds the defendant possibly

eligible for an earlier release date, the motion advances.                      At

stage two, the government, defense counsel and probation must "meet

to   discuss   the   case"   and     attempt   to     "reach   a    stipulat[ed]"

agreement.     And if that falls short, the district court, based on

the parties' memoranda, is charged with resolving the motion.

                        Marching To A Different Tune

             The AD 14-426 process seems as clear as a bell.                   And

yet, after Rodríguez filed his motion, the district court — for

whatever reason — ignored the process:                It leaped ahead of the

magistrate judge before he could chime in with an eligibility

determination, sua sponte denying the motion.                  As grounds for

rejecting the motion, the district court emphasized Rodríguez's

"maximum leader[ship]" role in "an elaborate drug trafficking

organization     that     operated     for     many    years       packaging   and

transporting over 9,000 kilos of cocaine."




      4A dissatisfied defendant may object to the magistrate
judge's eligibility determination to the presiding district judge
within 14 days.


                                      - 6 -
             Even so, about a month after the district court denied

Rodríguez's motion, the magistrate judge reviewed Rodríguez's

motion all the same.    And he determined Rodríguez may be eligible

for a lower sentence.5 So as AD 14-426 contemplates, the magistrate

judge handed the motion back to the district court for the next

stage of the process.

                                Rodríguez I

             The district court in a text order referencing its

initial denial again tossed Rodríguez's motion, rejecting the

magistrate judge's report and recommendation.         Twice spurned in

his quest for a sentence reduction, Rodríguez appealed his case to

us.   There, in Rodríguez I, we faced the question, among others,

of whether the district court had struck the wrong note by not

following its own internal, administrative rules, AD 14-426, when

it denied Rodríguez's motion.      See Rodríguez I, 854 F.3d 122.   And

we    said   yes.     Against     the   case's   backdrop   of   "unique

circumstances," we determined that "the prudent course" was to

vacate and remand, so the district court could comply with its own

administrative order in resolving Rodríguez's motion.       Id. at 126.

In explaining our reasoning, we noted that since Amendment 782 had

taken effect, the Puerto Rico district court had gained a good




      5The record does not reflect whether the magistrate judge
was aware of the district court's earlier rejection of Rodríguez's
motion.


                                   - 7 -
deal of experience handling sentence-reduction motions under AD

14-426.     Id. at 126.    Therefore we reasoned remand would permit

the district court to apply "the wealth of experience that it ha[d]

gained adjudicating motions to reduce sentences" under AD 14-426.

Id.     And finally, because the ultimate issue of whether to grant

a sentence reduction is a question Congress "committed to the

sentencing court's sound discretion," United States v. Zayas-

Ortiz, 808 F.3d 520, 523 (1st Cir. 2015), we uttered not a word on

"the proper outcome on remand."       Rodríguez I, 854 F.3d at 126.

            On the very same day we handed down our judgment in

Rodríguez I, the district court, seemingly on cue, swiftly heeded

the guidance we spelled out.          The district court ordered the

parties to "file their positions and recommendations as to whether

[Rodríguez's] sentence may be reduced pursuant to Amendment 782."

As AD 14-426 provides, the parties met a few days later to discuss

the case, hoping to reach a stipulated agreement. But to no avail.

So, consistent with the district court's administrative order, the

parties filed memoranda hewing to the court's deadline.

                   Still Marching To A Different Tune

            Having now dotted the "i's" and crossed the "t's," the

district court at last got its rightful turn to act under AD 14-

426.    And it missed nary a beat.    On the same day the parties filed

their    briefs,   the   district   court   denied   the   motion,   sending

Rodríguez away empty-handed for a third time.              As justification


                                    - 8 -
for the denial, the district court pointed yet again to its

original text order rejecting Rodríguez's motion.                     Regrettably,

when the district court denied Rodríguez's motion this last time,

the matter was still alive and well in our hands; we hadn't yet

issued our mandate returning the case to the district court.                       Of

course, the mandate did eventually issue – yet that happened

several days after the district court had already lowered the

baton.

                       Taking It From The Top Again

             That brings us to today's crescendo, marking round two

of this case before this court.            Rodríguez now appeals, advancing

three basic arguments.          Rodríguez first charges the district court

lacked     jurisdiction.         Next,    even   if   the    district    court    had

jurisdiction despite our unissued mandate, he claims the district

court abused its discretion in denying his motion.                      And to that

end, assuming we find an abuse of discretion, he lastly presses us

to remand his case to a different district court judge.                           The

government, for its part, disagrees in toto.                        We assess each

contention in turn, and along the way, note more facts as necessary

to   our   analysis.       But    when    all    is   said   and     done,   because

Rodríguez's assertions fall flat, we affirm.

                            The Divestiture Rule

             Because the district court denied Rodríguez's motion

before     this   court   had    issued    its   Rodríguez      I    mandate,    both


                                         - 9 -
Rodríguez and the government, singing from the same songsheet,

rightly agree that the court violated the divestiture rule.          This

rule provides that filing a notice of appeal, for the most part,

shifts "jurisdiction" from the district court to the court of

appeals.    Griggs v. Provident Consumer Disc. Co., 459 U.S. 56, 58

(1982).     But whether the district court order may all the same

stand is a bone of contention between the parties.

            To hear Rodríguez tell it, because the district court

lacked "jurisdiction" under the divestiture rule, the court's

denial order is a legal nullity, with no operative effect. Pushing

back, the government counters that the divestiture rule is not a

per se jurisdictional rule and so, because applying the rule here

would defeat its purpose of judicial economy, we shouldn't do so.

Reviewing de novo, see Fafel v. DiPaola, 399 F.3d 403, 410 (1st

Cir. 2005), we discern no reversible error.

                           Guiding Principles

           When a party files an appeal in a case, as mentioned

earlier, the divestiture rule ordinarily transfers the district

court's "jurisdiction" to the court of appeals.         United States v.

Maldonado-Rios, 790 F.3d 62, 64 (1st Cir. 2015)(citation omitted);

United     States   v.   Distasio,   820   F.2d   20,    23   (1st   Cir.

1987)(observing that "[a] docketed notice of appeal suspends the

sentencing court's power" to act).     And "until this court issue[s]

its mandate" for a decision, finalizing it, the district court


                                 - 10 -
does not reacquire "jurisdiction" over the case.        United States v.

Wells, 766 F.2d 12, 19 (1st Cir. 1985); United States v. Rush, 738

F.2d 497, 509 (1st Cir. 1984).

              But because the judge-made divestiture rule isn't based

on a statute, it's not a hard-and-fast jurisdictional rule.           See

Kontrick v. Ryan, 540 U.S. 443, 452-53 (2004)(observing that rules

of practice and procedure "do not create or withdraw federal

jurisdiction" because only Congress has the power to determine

subject-matter jurisdiction); United States v. Claiborne, 727 F.2d

842, 850 (9th Cir. 1984)(concluding that the divestiture rule isn't

jurisdictional because it's not based on a statute).           The rule,

rather, is rooted in concerns of judicial economy, crafted by

courts   to    avoid   the   confusion   and   inefficiency   that   would

inevitably result if two courts at the same time handled the same

issues in the same case.       See In re Padilla, 222 F.3d 1184, 1190

(9th Cir. 2000); United States v. Rodgers, 101 F.3d 247, 251 (2d

Cir. 1996).     Hence its application turns on concerns of efficiency

and isn't mandatory.     See, e.g., United States v. Leppo, 634 F.2d

101, 104 (3d Cir. 1980)(rejecting a "ritualistic application of

the divestiture rule"); 16A C. Wright, A. Miller, E. Cooper & C.

Struve, Federal Practice and Procedure, § 3949.1 n.53 (4th ed.

2018).

              We think applying the bench-made divestiture rule today

would surely short-circuit its aim of judicial efficiency, and


                                  - 11 -
here's why.   For one thing, as in Rodríguez I, we again wouldn't

be reaching the merits of the district court's denial order,

notwithstanding our otherwise "compelling interest in the finality

of litigation" and judgments.        Aybar v. Crispin-Reyes, 118 F.3d

10, 16 (1st Cir. 1997).     For another thing, with jurisdiction back

in its hands, the district court, undoubtedly, would again deny

Rodríguez's motion, like every other time it has confronted — and

denied — the motion.   And then, chances are that Rodríguez would

once more appeal his case to us.        Which would present to us the

third variation on the original theme of this case, like an encore,

featuring the very same parties, the very same motion, the very

same denial order, and the very same arguments on the merits. That

seems to us too much to ask of a rule fashioned to ferret imprudence

out of the courts.     See 20 Moore's Federal Practice - Civil §

303.32   (2018)(reasoning     that    courts   ought   not   apply   the

divestiture rule when doing so results only in "needless paper

shuffling"); see, e.g., United States v. Hickey, 580 F.3d 922, 927

(9th Cir. 2009)(opting against application of the divestiture rule

when "no useful purpose would be served by requiring" the district

court "to redecide the . . . motions")(citation omitted).       And so,




                                 - 12 -
we decline to apply the divestiture rule to Rodríguez's claim and

thus proceed to our merits review.6

                      The Motion on its Merits

          Even if the district court had jurisdiction over the

motion, Rodríguez posits the district court abused its discretion

by denying it.    He advances four broad arguments.    Rodríguez's

lead contention faults the district court for improperly balancing

the 18 U.S.C. § 3553(a) factors, particularly those favoring a

reduction.7   Next he blasts the district court for coldshouldering


     6   Let us be crystal-clear:     Nothing in our opinion today
should be taken as giving district courts the green light to ignore
the divestiture rule. The district court in this case rushed the
process; it should've awaited our mandate before acting.
Ordinarily, our practice in such cases is to vacate the early entry
of a district court's order and remand "so that the district court,
once    its    jurisdiction   has  reattached,  may  consider   the
issue . . . anew."   United States v. George, 841 F.3d 55, 72 (1st
Cir. 2016).      But because the district court here has clearly
demonstrated no interest in lowering the defendant's sentence, as
explained above, following our usual protocol today would be a
waste of time. This opinion is therefore confined wholly to the
narrow facts animating the case before us, and in no way diminishes
the importance of compliance with the divestiture rule.

     7  The § 3553(a) factors include: (1) the nature and
circumstances of the offense and the history and characteristics
of the defendant; (2) the need for the sentence imposed to reflect
the seriousness of the offense, to promote respect for the law,
and to provide just punishment for the offense; (3) the need for
the sentence imposed to afford adequate deterrence; (4) the need
to protect the public; (5) the need to provide the defendant with
educational or vocational training or medical care; (6) the kinds
of sentences available; (7) the Sentencing Guidelines range; (8)
the pertinent policy statements of the Sentencing Commission; (9)
the need to avoid unwanted sentencing disparities; and (10) the
need to provide restitution to victims. See 18 U.S.C. § 3553(a).



                               - 13 -
his post-sentencing conduct.    Then he assails the district court

for grounding its denial order on "factors that had already been

accounted for."    And lastly, he contends the denial of his motion

resulted in an unwarranted sentencing disparity between him and a

codefendant.8     The government sees it otherwise.   Reviewing the

denial of Rodríguez's 18 U.S.C. § 3582(c)(2) motion for abuse of

discretion, see United States v. Vaughn, 806 F.3d 640, 642 (1st

Cir. 2015), we perceive no error.9

                          Guiding Principles

          A federal court by and large "may not modify a term of

imprisonment once it has been imposed."   18 U.S.C. § 3582(c).   But




     8 Rodríguez also maintains that the district court failed to
properly follow AD 14-426 because the court failed to use "Form AO
247 in his denial."         That contention is a non-starter.
Unfortunately for Rodríguez, because he advances this argument for
the first time in his reply brief – and nowhere else – we deem it
waived.   See Sandstrom v. ChemLawn Corp., 904 F.2d 83, 86 (1st
Cir. 1990)(holding that an argument "not made to the district court
or in appellant's opening brief, [but] surfacing only in his reply
brief" is waived).

     9In the "Summary of the Argument" part of his brief, Rodríguez
asserts, among other things, that the district court failed to
"consider[] the guiding principles and policy statement in USSG §
1B1.10." Yet Rodríguez never fleshes out this argument. To the
extent Rodríguez is referring to the district court's failure to
either (1) assess any danger his early release may pose or (2)
consider evidence of his post-sentencing conduct, we address both
those issues above.      But if Rodríguez is making different
arguments, because he fails to develop these contentions later in
his brief, we need not address them. See, e.g., United States v.
Trinidad–Acosta, 773 F.3d 298, 310 n.5 (1st Cir. 2014) (deeming
waived arguments alluded to in the brief's summary-of-the-argument
section but not developed elsewhere).


                                - 14 -
if the Sentencing Commission reduces a defendant's sentencing

guidelines range, Congress permits a federal court to reduce the

defendant's term of imprisonment, "after considering the factors

set forth in [§] 3553(a) . . . if such a reduction is consistent

with applicable policy statements" issued by the Commission.                     18

U.S.C. § 3582(c)(2).         Section 3582, however, in no way creates a

right   to   a    sentence   reduction.        See   USSG    §   1B1.10   comment.

(backg'd.)       (mentioning   that    a   reduction        under   §   1B1.10   is

discretionary and "does not entitle a defendant to a reduced term

of imprisonment as a matter of right").

             In determining whether a defendant should receive a

sentence reduction, the district court must engage in a two-step

inquiry.     It first must determine "'the amended guideline range

that would have been applicable to the defendant' had the relevant

amendment been in effect at the time of the initial sentencing."

Dillon v. United States, 560 U.S. 817, 827 (2010)(quoting USSG §

1B1.10(b)(1)).       The court then must weigh the § 3553(a) factors

"and determine whether, in its discretion, the reduction" is

"warranted in whole or in part under the particular circumstances

of the case."        Id.     In addition to the § 3553(a) factors, the

district court "shall consider the nature and seriousness of the

danger to any person or the community that may be posed by a

reduction in the defendant's term of imprisonment." USSG § 1B1.10,

comment. (n.1(B)(i-iii)).          And the court "may consider post-


                                      - 15 -
sentencing conduct of the defendant."          Id.   "[P]roceedings under

18   U.S.C.    [§]   3582(c)(2)   and   [§   1B1.10],"   however,   "do   not

constitute a full resentencing of the defendant."          § 1B1.10(a)(3).

                          The Pertinent Factors

              Before deciding Rodríguez's motion, the district court

had before it Rodríguez's original and reduced guidelines ranges.

And the court had at its disposal the parties' "positions and

recommendations as to whether defendant's sentence may be reduced

pursuant to Amendment 782."       The parties, including Rodríguez, in

their briefs addressed the § 3553(a) factors; what, if any, danger

Rodríguez's early release posed; his mitigating post-sentencing

conduct; his educational efforts, his completion of a drug abuse

program; and a letter of good behavior from his prison counselor.

And in a similar vein, pointing to § 1B1.10, the government's brief

expressly advised the district court it had to consider all the §

3553(a) factors.      In declining to reduce Rodríguez's sentence, the

district court explicitly stated that it had made its decision

with "the benefit of the positions of the defendant (Docket No.

1533), the probation officer (Docket No. 1534) and the government

(Docket No. 1535)."10

              We see no basis for reversal.      So long as the district

court's order and the record as a whole reflects that it considered


      10
       Rodríguez laments that "[t]he district court's line order"
denying his motion was "terse[]," and therefore, insufficient.


                                   - 16 -
all the pertinent factors — as here — we can safely assume it did

so. See, e.g., United States v. Vargas–Dávila, 649 F.3d 129, 130

(1st Cir. 2011); United States v. Dávila–González, 595 F.3d 42,

48–49 (1st Cir. 2010); United States v. Turbides–Leonardo, 468

F.3d 34, 40–41 (1st Cir. 2006).        Thus contrary to Rodríguez's

suggestion, that the district court highlighted some factors but

not others in its denial order doesn't mean the court closed its

eyes to them.   What that suggests, on the contrary, is that the

district court may have been unimpressed or unpersuaded by the

relevant factors it didn't reference.        See United States v.

Morrisette, 429 F.3d 318, 325 (1st Cir. 2005)(citing United States

v. Martins, 413 F.3d 139, 154 (1st Cir. 2005)).         Our caselaw

doesn't require district courts to "mention every § 3553(a) factor

nor intone any particular magic words."     United States v. Denson

689 F.3d 21, 28 (1st Cir. 2012)(citation omitted).   Most plausible

is that the district court found particularly glaring Rodríguez's




This is not reversible error. We have held numerous times that
"brevity must not be mistaken for inattention — especially so when,
as here, the sentence falls within guideline range." United States
v. Garay-Sierra, 832 F.3d 64, 68 (1st Cir. 2016) (internal
quotation marks and citation omitted); see also United States v.
Turbides–Leonardo, 468 F.3d 34, 40 (1st Cir. 2006) ("While the
court ordinarily should identify the main factors upon which it
relies, its statement need not be either lengthy or detailed.")
(citing United States v. Navedo-Concepción, 450 F.3d 54, 58 (1st
Cir. 2006)). So too here.




                              - 17 -
"maximum" leadership role, the ginormous amount of drugs he and

his group trafficked, the many years the organization operated,

and the intricacy of the conspiracy.

             Enough said on this; on to the post-sentencing issue.

                 Post-Sentencing Rehabilitation Evidence

             For his next fanfare, hanging his hat on Pepper v. United

States, 562 U.S. 476 (2011), Rodríguez takes the district court to

task for failing to consider his post-sentencing rehabilitation

evidence.     He points to a "detailed letter [from his counselor at

the detention center] that one does not ordinarily see was provided

to the district court," arguing the district court should have,

but failed to, consider it.             Multiple errors plague this line of

reasoning.     As a preliminary matter, as we said earlier, simply

because the district court didn't expressly mention Rodríguez's

rehabilitative evidence doesn't mean it didn't consider it; the

record   shows    the   district       court     adequately    reviewed   all   the

evidence before it, which included Rodríguez's post-sentencing

conduct and the letter from his detention center counselor.                     See

Morrisette, 429 F.3d at 325.

             Regardless,       even     if   the    district     court    had   not

considered any of Rodríguez's rehabilitative evidence, Pepper is

inapt.    In that case, the Supreme Court clarified that a district

court    confronted     with    a     "resentencing"    motion    "may    consider

evidence of the defendant's post-sentence rehabilitation."                  Id. at


                                        - 18 -
490.        Pepper   is   a   case   about   resentencing,   so   it   does   not

necessarily follow it holds sway in this case — a case about

reducing a sentence under § 3582(c)(2).11               See § 1B1.10(a)(3);

Dillon, 560 U.S. at 825-28 (holding that United States v. Booker,

543 U.S. 220 (2005), has no bearing on § 3582(c) proceedings);

see, e.g., United States v. Meridyth, 701 F. App'x 722, 725 (10th

Cir. 2017), cert. denied, 138 S. Ct. 2002 (2018)(concluding that

Pepper has no bearing on § 3582(c)(2) sentence-reduction motions).

              But in any event, even if Pepper was apt, it is a given

that it would not get Rodríguez far:            No one — not even Rodríguez

himself — contests that Pepper plainly says that a district court

"may," not must, consider post-sentencing conduct.12               Pepper, 562


       11
        Throughout Dillon, the Supreme Court numerous times
explains that § 3582(c)(2) sentence-reduction proceedings are
different from the "resentencing" proceedings at issue in Pepper.
560 U.S. at 825 ("The language of § 3582(c)(2) belies Dillon's
characterization of proceedings under that section. By its terms,
§ 3582(c)(2) does not authorize a sentencing or resentencing
proceeding."); id. at 826 ("Section 3582(c)(2)'s text, together
with its narrow scope, shows that Congress intended to authorize
only a limited adjustment to an otherwise final sentence and not
a plenary resentencing proceeding."); id. at 827 ("Because
reference to § 3553(a) is appropriate only at the second step of
this circumscribed inquiry, it cannot serve to transform the
proceedings under § 3582(c)(2) into plenary resentencing
proceedings."); id. at 831 ("As noted, § 3582(c)(2) does not
authorize a resentencing. Instead, it permits a sentence reduction
within the narrow bounds established by the Commission."); see
also Pepper, 562 U.S. at 490 (pointing to the part of Dillon
distinguishing   between   §   3582(c)(2)   "sentence-modification
proceedings" and "plenary resentencing proceedings").

       12
       Section 1B1.10's commentary further proves the point. It
requires the district court only to weigh public safety factors,


                                       - 19 -
U.S. at 490; see, e.g., United States v. Navarro, 693 F. App'x

459, 460 (7th Cir. 2017)("A district court may take into account

post-sentencing efforts at rehabilitation in deciding whether a

lower sentence is appropriate under § 3582(c)(2), but the court is

not required to do so.")(emphasis added); United States v. Parker,

762 F.3d 801, 812 (8th Cir. 2014)(explaining that Pepper does not

oblige a district court faced with a resentencing to give lower

sentences in light of rehabilitation evidence);            see also Black's

Law Dictionary (10th ed. 2014)(defining the term "may" as "to be

permitted to" do something).         Therefore despite Rodríguez's "44

pages   of    documentation"         detailing       his    post-sentencing

rehabilitative conduct, although we might applaud his efforts,

unfortunately for him, because nothing required the district court

to weigh such mitigating evidence, we detect no error here.

Davila-Gonzalez,   595   F.3d   at   49   ("Merely    raising   potentially

mitigating factors does not guarantee a lesser sentence."); see

also United States v. Anonymous Defendant, 629 F.3d 68, 78 (1st

Cir. 2010)(remarking that a district court's failure to assign




while it merely "permits," not mandates, the district court to
consider post-sentencing conduct when reviewing a sentence-
reduction motion under § 3582(c)(2).


                                 - 20 -
particular significance to a specific mitigating factor is not of

reversible magnitude).

                  Counting Accounted-For Factors

          Rodríguez   next   seems   to    contend   the   district   court

couldn't base its denial of his motion on his "participation and

leadership role in the conspiracy," because those "were explicitly

taken into account not only in the plea agreement, but also in the

PSR calculation of the sentencing guidelines, and by the district

court at the time of sentencing."         He relies on United States v.

Rosa-Martínez, a non-binding district court opinion.         108 F. Supp.

3d 15, 16 (D.P.R. 2015).     This reliance is misplaced.       Nowhere in

Rosa-Martínez does the district court say, let alone imply, that

in deciding whether to grant a § 3582(c)(2) reduction, a district

court cannot consider the circumstances of a defendant's crime.

And we decline to do so here. Accepting Rodríguez's argument would

certainly run smack up against the plain and unambiguous language

of § 3582's directive to consider "the factors set forth in section

3553(a) to the extent that they are applicable," which includes

(relevant here) "the nature of circumstances of the offense." See,

e.g., United States v. Monday, 390 F. App'x 550, 554-55 (6th Cir.

2010)(rejecting the argument that "a defendant's post-sentencing

conduct may not be considered in determining whether to grant

a . . . § 3582(c)(2)" motion, because that would "fly in the face"

of clear congressional directives).        The bottom line is, because


                                - 21 -
Rodríguez has failed to show how the district court's consideration

of his "participation and leadership role in the conspiracy" was

an abuse of discretion, we spot no error on this basis.

                        Sentencing Disparity

          For his final argument, when the district court denied

his sentence-reduction motion but granted Luis Padilla-Pérez's, a

coconspirator's, sentence-reduction motion, Rodríguez frets that

the court created an unwarranted disparity and so erred.           But

Rodríguez's concern doesn't sing to us.    Rodríguez first sketches

this argument in a barebones way, in the "Statement of the Case"

section of his brief.   But he fails later in his brief to put meat

on the bones of his skeletal disparity contention.     For instance,

although Rodríguez tells us he and Padilla-Pérez pleaded guilty to

trafficking the same amount of drugs as well as that they both

received a leadership role enhancement, he says nothing about "this

coconspirator's   specific   criminal   involvement,   his    criminal

history, his career offender status, or his cooperation (if any)

with the government."   United States v. Rodríguez-Adorno, 852 F.3d

168, 177 (1st Cir. 2017).    And he mentions zippo about what sort

of leadership role enhancement Padilla-Pérez received.       He doesn't

even furnish us with Padilla-Pérez's sentence.

          On this scant record, we cannot reach a "determination

that he and his proposed comparator[] are similarly situated."

Id. (citing United States v. Reyes-Santiago, 804 F.3d 453, 467


                               - 22 -
(1st Cir. 2015)). A charge that the district court erred — pressed

singularly in the "Statement of the Case" section of an appellant's

brief yet not later renewed and developed in the "Argument" section

— hardly offers us enough to review on appeal.               See Fed. R. App.

P. 28(a) (commenting that an appellant's brief must contain both

a   statement   of   the    case    and   appellant's   argument     —    "under

appropriate headings" — and that the argument must spell out the

"appellant's contentions and the reasons for them"). Judges, after

all, "are not expected to be mindreaders."                   United States v.

Zannino, 895 F.2d 1, 17 (1st Cir. 1990). And so, because Rodríguez

makes his sentencing-disparity assertion "in a perfunctory manner,

unaccompanied by some effort at developed argumentation," it is

"waived."    Id.

            Even if Rodríguez hadn't waived his sentencing-disparity

argument, it still would be unavailing.           For starters, a district

court's consideration of sentencing disparity is aimed primarily

at the "minimization of disparities among defendants nationally,"

not disparities among codefendants, and yet Rodríguez advances no

such comparator argument.          United States v. Floyd, 740 F.3d 22, 39

(1st Cir. 2014) (quoting United States v. Vargas, 560 F.3d 45, 52

(1st Cir. 2009)).     Putting that aside — as to his argument that he

suffered disparate treatment compared with Padilla-Pérez — the

record evidence belies this contention.           The district court ably

found   Rodríguez    to    be   more    blameworthy   than    all   his   fellow


                                       - 23 -
confederates, including Padilla-Pérez.    It found, in particular,

that Rodríguez was "the maximum leader" of the conspiracy.     See

USSG § 3B1.1(a) (directing four-level enhancement for organizer or

leader).   Even Rodríguez's plea agreement dubs him as "the Leader"

of "the Wilfredo Rodríguez-Rosado drug trafficking organization."

In short, "it is too obvious to warrant citation of authority that

an offender who sits at the top of a criminal hierarchy is not

similarly situated to his underlings."     Floyd, 740 F.3d at 39.

Thus even on the merits, we find no abuse of discretion.

                              Finale

           Having carefully worked our way through all the issues,

with the stage curtain lowering, we affirm the district court's

order denying Rodríguez's sentence-reduction motion.13




     13Because we detected no abuse of discretion, and thus aren't
vacating and remanding, we don't reach the question of whether a
different district judge should resolve the motion.


                              - 24 -
