                         UNPUBLISHED

UNITED STATES COURT OF APPEALS
                FOR THE FOURTH CIRCUIT


UNITED STATES OF AMERICA,               
                 Plaintiff-Appellee,
                 v.                             No. 03-4024
CHRISTOPHER LAMONT HILL,
              Defendant-Appellant.
                                        
UNITED STATES OF AMERICA,               
                 Plaintiff-Appellant,
                 v.                             No. 03-4098
CHRISTOPHER LAMONT HILL,
               Defendant-Appellee.
                                        
           Appeals from the United States District Court
         for the Eastern District of Virginia, at Richmond.
            Richard L. Williams, Senior District Judge.
                            (CR-02-59)

                      Argued: October 31, 2003

                       Decided: April 2, 2004

          Before WILKINS, Chief Judge, and KING and
                  GREGORY, Circuit Judges.



Affirmed in part, vacated in part and remanded with instructions by
unpublished opinion. Judge Gregory wrote the opinion, in which
Chief Judge Wilkins and Judge King joined.
2                        UNITED STATES v. HILL
                              COUNSEL

ARGUED: Frederick Hope Marsh, HILL, TUCKER & MARSH,
Richmond, Virginia, for Appellant. Paul Joseph McNulty, United
States Attorney, Alexandria, Virginia, for Appellee. ON BRIEF:
Brent A. Jackson, HILL, TUCKER & MARSH, Richmond, Virginia,
for Appellant. Michael J. Elston, Assistant United States Attorney,
Alexandria, Virginia, for Appellee.



Unpublished opinions are not binding precedent in this circuit. See
Local Rule 36(c).


                              OPINION

GREGORY, Circuit Judge:

   Christopher Lamont Hill appeals his convictions and sentence for
conspiracy to possess with intent to distribute and to distribute pow-
der cocaine and cocaine base, in violation of 21 U.S.C. §§ 846, 851;
possession with intent to distribute cocaine base, in violation of 21
U.S.C. §§ 841, 851; two counts of distribution of cocaine base, in vio-
lation of 21 U.S.C. §§ 841, 851; possession of a firearm in furtherance
of a drug trafficking crime, in violation of 18 U.S.C. § 924(c); and use
of a communication device to facilitate a drug trafficking crime, in
violation of 21 U.S.C. § 843(b). Hill was sentenced to a total of 444
months on these convictions. The district court, however, refused to
sentence Hill to a mandatory minimum of life imprisonment, pursuant
to 21 U.S.C. § 841(b)(1)(A), based on Hill’s prior convictions.
Instead, the district court held that the government’s filing of a 21
U.S.C. § 851 notice of enhancement constituted vindictive prosecu-
tion, and sentenced Hill under the United States Sentencing Guide-
lines.

   Hill appeals contending that all six convictions should be dismissed
because his Fifth Amendment rights were violated through prosecu-
torial vindictiveness. In the alternative, he requests that we vacate his
                        UNITED STATES v. HILL                         3
sentence and remand to the district court for resentencing with
instructions that the district court had authority to downwardly depart
from the guidelines. The United States cross-appeals, asserting that
the district court erred by finding prosecutorial vindictiveness and
thus refusing to enhance Hill’s sentence pursuant to 21 U.S.C. §
841(b)(1)(A), which would have required the imposition of a manda-
tory minimum life sentence.

   We reject Hill’s argument that all six counts upon which he was
convicted should be dismissed because the superseding indictment
amounted to vindictive prosecution. Therefore, we affirm Hill’s
underlying convictions. Similarly, we reject his argument regarding
downward departure. On the cross-appeal, however, we find that
ambiguities in the district court’s finding of vindictive prosecution
require us to remand for plenary consideration of the issue. Further-
more, we conclude that the district court erred in treating its finding
of vindictive prosecution as an irrebuttable presumption. Therefore,
we vacate and remand for plenary consideration of the sentencing
issue raised in the government’s cross-appeal.

                                   I.

   On December 18, 2001, the government filed a one-count indict-
ment against Joseph Wayne Pratt, charging him with possession with
intent to distribute more than fifty grams of cocaine base, in violation
of 28 U.S.C. § 841(a). The district court dismissed the indictment
with prejudice because of the government’s failure to prosecute. On
February 20, 2002, a federal grand jury in Richmond issued a six-
count indictment against Pratt, Mark Beale, and Defendant Hill.

   Hill was indicted on Counts One and Two: (1) conspiracy to pos-
sess with the intent to distribute and to distribute more than 50 grams
of powder cocaine and cocaine base, in violation of 21 U.S.C. § 846,
and (2) possession with the intent to distribute and distribution of
more than 50 grams of cocaine base, in violation of 21 U.S.C.
§ 841(a)(1) and 18 U.S.C. § 2. Pratt was indicted on all six counts and
Beale was indicted on the first and third counts.1
  1
   Counts Three through Five consisted of attempts to possess with the
intent to distribute powder cocaine and cocaine base, in violation of 21
U.S.C. §§ 841(a)(1), 846, and 18 U.S.C. § 2, and Count Six charged
using a communication device to facilitate a drug trafficking crime, in
violation of 21 U.S.C. § 843(b).
4                         UNITED STATES v. HILL
   Before trial, the United States successfully moved to dismiss Count
Two against Hill without prejudice. Beale entered an agreement to
plead guilty to Count Three. On June 20, 2002, Pratt and Hill pro-
ceeded to trial on the remaining counts. At trial, Pratt filed a motion
in limine and for severance challenging the government’s ability to
bring a distribution count as an overt act separate from the conspiracy
count. The distribution count arose from an incident on October 29,
1999, where Hill allegedly sold crack to Pratt. Pratt’s counsel argued
that the October 29 incident was based on the same underlying facts
as the count in the original indictment which had been dismissed with
prejudice. Pratt also moved to exclude certain tapes and transcripts of
recorded conversations.2 The district court denied the omnibus
motions to exclude tapes and transcripts of recorded conversations,
but excluded all evidence corresponding to Count Two, which was
based on the events of October 29, 1999. The court reasoned that
Count Two against Pratt directly related to the original indictment
against Pratt, which had already been dismissed with prejudice, and
directly related to the previously dismissed Count Two against Hill.
The district court denied the government’s efforts to seek a continu-
ance to file an interlocutory appeal challenging the court’s severance
and exclusion of evidence.

   At trial, the jury convicted Pratt on Count One and Counts Three
through Six. Because of the successful motion in limine challenging
evidence relating to the events of October 29, the evidence against
Hill on Count One, the conspiracy charge, was limited. The jury hung
as to Count One against Hill. The district court declared a mistrial and
set a new trial date of September 18, 2002.

   On August 20, 2002, a grand jury returned a six-count superseding
indictment against Hill. The two counts upon which Hill was origi-
nally charged were reinstated, and the government added four addi-
tional counts.3 On September 16, 2002, two days before trial, the
   2
     While it is unclear whether Hill joined Pratt’s motion at this juncture,
Hill subsequently relied on the ruling granting this motion when seeking
to have certain evidence excluded.
   3
     The new counts were as follows: (3-4) possession with intent to dis-
tribute and distribution of cocaine base, in violation of 21 U.S.C.
§ 841(a)(1); (5) possession of a firearm in furtherance of a drug traffick-
ing crime, in violation of 18 U.S.C. § 924(c); and (6) use of a communi-
cation device in furtherance of a drug trafficking crime, in violation of
21 U.S.C. § 843(b).
                        UNITED STATES v. HILL                         5
government filed a notice of intent to seek sentencing enhancement,
21 U.S.C. § 851. Such enhancement would require mandatory mini-
mum life sentences on Counts One and Two of the indictment, pursu-
ant to § 841(b)(1)(A), based on Hill’s three prior felony drug
convictions. The defense did not object to the enhancement notice.

    On the day of trial, Hill unsuccessfully moved to quash the counts
in the superseding indictment, "object[ing] on the basis that there is
no corroborating evidence." The court asked defense counsel, "are
you claiming prosecutorial misconduct in adding these, or what?"
Hill’s counsel responded, "I won’t go that far, Your Honor. I just have
a problem with there being no corroborative testimony or evidence
. . . ." (J.A. 305.)

  Following a one-day bench trial, Hill was convicted on all counts.
Before sentencing, Hill obtained new counsel (who now represents
Hill on appeal), and filed a motion for departure from the sentencing
guidelines, pursuant to 18 U.S.C. § 3553, on the basis that sentencing
him under the career offender guideline over-represented the serious-
ness of his criminal history. Hill also objected to the Presentence
Report, claiming that the report misstated one of his prior convictions.

   At the sentencing hearing, the district court denied Hill’s motions.
However, in sentencing Hill, the district court denied what it con-
strued as the government’s "motion" for an enhanced sentence pursu-
ant to 21 U.S.C. § 841(b)(1)(A). The court did so based upon a sua
sponte finding of vindictive prosecution. The district court stated the
new charges and the enhancement were:

    over-kill of the first order. And to add insult to injury, that
    the government would be belligerent enough to really ask
    for an enhancement on about the third superseding indict-
    ment in the case simply because they are ticked off at the
    Court because I made an adverse evidentiary ruling for them
    and dismissed a count because they weren’t ready to go to
    trial when they were scheduled to go, and they are taking it
    out on your client, frankly, it is a sad commentary on our
    judicial system that the government can manipulate it in
    such a way.
6                        UNITED STATES v. HILL
    ....

    The government filed additional charges and sought the
    enhancement only after The Court’s evidentiary ruling and
    the jury’s failure to reach a verdict against Hill in the first
    trial. I find that this is a classic case of vindictiveness by the
    prosecution. The government’s action in seeking the sen-
    tence enhancement only on the second trial, even though all
    the raw material to do so was available to the government
    during the first trial, proves that the government was moti-
    vated by animus.

(J.A. 509, 516 (emphasis added).)

   Accordingly, the court sentenced Hill under the guideline ranges
rather than imposing the mandatory minimum life sentences, pursuant
to 21 U.S.C. § 841(b)(1)(A), on Counts One and Two that would have
flowed from the government’s filing of § 851 information. By written
order, the district court sentenced Hill to 444 months of imprison-
ment, consisting of 360 months on Counts One through Three, 240
months on Count Four, and 48 months on Count Six, all to run con-
currently, and 84 months on Count Five to run consecutively. Follow-
ing sentencing, this appeal and cross-appeal ensued.

                                   II.

   Hill raises two arguments premised on a theory of vindictive prose-
cution. First, he contends that we should dismiss all six of his under-
lying convictions because the government, by filing the superseding
indictment, engaged in vindictive prosecution thus violating Hill’s
Fifth Amendment rights. Alternatively, Hill argues that even if we do
not set aside his convictions, we should affirm the district court’s dis-
missal of the § 851 enhancement based on its finding of vindictive
prosecution.

   The prosecutorial vindictiveness doctrine arose from a series of
cases concerning the due process violation that occurs when a defen-
dant is punished for exercising constitutional or statutory rights in his
or her defense. See North Carolina v. Pearce, 395 U.S. 711, 723-728
                         UNITED STATES v. HILL                         7
(1969) (finding a presumption of vindictiveness where the judge
imposed a more severe sentence after a new trial). The Supreme Court
has held that to punish "a person because he has done what the law
plainly allows him to do is a due process violation of the most basic
sort, [citation] and for an agent of the State to pursue a course of
action whose objective is to penalize a person’s reliance on his legal
rights is ‘patently unconstitutional.’" Bordenkircher v. Hayes, 434
U.S. 357, 363 (1978) (citations omitted). In the prosecutorial context,
the doctrine holds that a due process violation occurs when a prosecu-
tor takes action to penalize a defendant for invoking a legally pro-
tected right. See Blackledge v. Perry, 417 U.S. 21, 28-29 (1974).

   In Blackledge, the defendant exercised his right to a new trial fol-
lowing a conviction for misdemeanor assault. Thereafter, the prosecu-
tor charged him with felony assault based on the same conduct. The
Court held that the felony charge was barred on due process grounds.
The Court stated that "the Due Process Clause is not offended by all
possibilities of increased punishment upon retrial after appeal, but
only by those that pose a realistic likelihood of ‘vindictiveness.’" Id.
at 27 (emphasis added). In Blackledge, the Court stressed that a pre-
sumption was appropriate even absent "evidence that the prosecutor
in this case acted in bad faith or maliciously," id. at 28, because the
mere appearance of vindictiveness would chill the right to appeal. See
also United States v. Goodwin, 457 U.S. 368, 373-78 (1982).

   In Bordenkircher, supra, and Goodwin, supra, the Court reviewed
prosecutorial vindictiveness claims arising from defendant’s assertion
of protected rights in the pretrial context. In those cases, the prosecu-
tors indicted defendants on more serious charges after the defendants
rejected plea bargains. In Bordenkircher, the Court held that no pre-
sumption of vindictiveness arose because in the "give-and-take" of
plea bargaining, there is no retaliation so long as the defendant
remains free to accept or reject the plea. 434 U.S. at 363. Similarly,
in Goodwin, the Court rejected defendant’s claim that a presumption
of vindictiveness arose when the defendant refused to plead guilty and
demanded a jury trial. See 457 U.S. at 383.

   The reasonable likelihood standard is to be distinguished from an
actual showing of vindictiveness. In United States v. Wilson, 262 F.3d
305 (4th Cir. 2001), we stated that to establish actual prosecutorial
8                        UNITED STATES v. HILL
vindictiveness, the defendant "must show, through objective evi-
dence, that (1) prosecutor acted with genuine animus toward the
defendant and (2) the defendant would not have been prosecuted but
for that animus." Id. at 314 (citing Goodwin, 457 U.S. at 380 n.12).
Wilson recognizes, as discussed above, that if the defendant cannot
demonstrate such animus, he or she may still present evidence of "cir-
cumstances from which an improper vindictive motive may be pre-
sumed." Id.

   Hill argues that all six of his underlying convictions should be set
aside because the government engaged in vindictive prosecution.4 We
find Hill’s argument unavailing.

   First, Hill does not articulate whether his vindictive prosecution
claim is one of actual animus, or if it is of the "reasonable likelihood
of vindictiveness" ilk. Regardless, in the first instance, Hill presents
no objective evidence that the prosecutor acted with genuine animus,
and that "but for" such animus Hill would not have been prosecuted.
Wilson, 262 F.3d at 314. Furthermore, we find that on these facts,
bringing additional charges following a mistrial does not raise the
"reasonable likelihood of vindictiveness." As the Sixth Circuit has
recognized, "[g]enerally, a potentially vindictive superseding indict-
ment must add additional charges or substitute more severe charges
based on the same conduct charged less heavily in the first indict-
ment." United States v. Suarez, 263 F.3d 468, 480 (6th Cir. 2001)
(citation omitted). Here, however, it was not the additional counts of
the indictment that would have subjected Hill to the greatest punish-
ment. Instead, it was Counts One and Two of the superseding indict-
ment, counts upon which Hill was originally indicted, that carried the
heaviest penalties — mandatory minimum life sentences if the gov-
    4
   The government contends that under United States v. Olano, 507 U.S.
725, 731-34 (1993), we have no authority to review this prosecutorial
vindictiveness claim because it was waived by the defendant. See Br. of
Gov’t at 14-15 (citing J.A. 305-07). The colloquy on which the govern-
ment relies, however, does not support its waiver argument. In that collo-
quy, defense counsel disavowed any allegation of prosecutorial
misconduct, but did so within the context of whether the new charges
were supported by sufficient evidence, not whether the United States
acted with vindictive motive.
                         UNITED STATES v. HILL                          9
ernment filed a § 851 notice of enhancement. Thus, Hill cannot rea-
sonably claim that the additional charges alone raised a presumption
of vindictiveness, for the additional charges carried penalties that
were largely cumulative. See Lane v. Lord, 815 F.2d 876, 879 (2d Cir.
1987) (holding no presumption of vindictiveness despite additional
charges following mistrial because the defendant was not exposed to
any more serious criminal penalties).

   Moreover, even with a modest increase in potential penalty because
the sentence under Count Five runs consecutively, the additional
charges appear to manifest the government’s legitimate response to
new circumstances occasioned by the adverse evidentiary ruling and
mistrial. As a result of the court’s evidentiary ruling in the first trial
concerning the events of October 29, the government naturally sought
to proffer additional overt acts upon which it could base the original
conspiracy count and obtain a conviction. In advance of the new trial,
the United States took the opportunity to "cure perceived deficiencies
in the original indictment" that contributed to the mistrial. United
States v. Brown, 298 F.3d 392, 406 (5th Cir. 2002) (internal quotation
marks omitted). As the government states in its brief, "[b]y charging
the overt acts of the conspiracy as separate counts (including the use
of a firearm and the use of a pager), the United States was reasonably
assured that the evidence regarding those substantive counts would
not be excluded from a second trial." Br. of Gov’t at 17. This wholly
neutral, and rational, reason for the additional charges defeats the pre-
sumption of vindictiveness. Accordingly, Hill’s contention that all six
convictions should be dismissed because of prosecutorial vindictive-
ness is without merit.

                                   III.

   Hill argues on appeal that the district court erred by refusing to
downwardly depart in sentencing. Hill claims that the district court
"had the authority to downwardly depart . . . but failed to do so
because it believed it did not have the authority to do so." Appellant’s
Br. at 21; see United States v. Jones, 18 F.3d 1145, 1148-49 (4th Cir.
1994) (noting that district court’s refusal to downwardly depart is not
subject to appellate review unless the court mistakenly believed that
it lacked the authority to depart).
10                        UNITED STATES v. HILL
   In sentencing Hill, the district court remarked, "I am imposing this
sentence with a heavy heart because I happen to think it is so dispro-
portionate to what the sentence ought to be. I want the record to
reflect that." From the record, it is clear that the district court refused
to downwardly depart, not because it believed it lacked authority, but
because it found departure unwarranted. The district court concluded
that there was "no reason to depart from the sentence called for by the
Guidelines . . . . The defendant is correctly classified as a Career
Offender, and his criminal history is not so atypical from that of other
Career Offenders to warrant a departure . . . ." Dist. Ct. Findings of
Fact ¶ 10 (E.D. Va. Dec. 10, 2002). Therefore, we reject Hill’s con-
tention that the district court erred in refusing to downwardly depart.

                                    IV.

                                    A.

   On cross-appeal, the United States argues that the district court
erred by holding that the filing of the § 851 enhancement on the eve
of retrial constituted vindictive prosecution. The government contends
the district court’s sua sponte finding of vindictiveness cannot be sup-
ported under either the actual animus or the reasonable likelihood of
vindictiveness standard. We review a district court’s finding regard-
ing prosecutorial vindictiveness for abuse of discretion. United States
v. Fiel, 35 F.3d 997, 1007 (1994) (citation omitted); accord United
States v. Perry, 335 F.3d 316, 320 (4th Cir. 2003) (citing United
States v. Najjar, 300 F.3d 466, 480 (4th Cir. 2002)).

   The United States argues that the district court erred in purporting
to "dismiss" the sentencing enhancement, because the "government’s
discretionary authority to file a Section 851 notice is virtually abso-
lute and unreviewable."5 Br. of Gov’t at 26. However, the government
  5
   Section 851(a)(1) of Title 21 of the United States Code provides: "No
person who stands convicted of an offense under this part shall be sen-
tenced to increased punishment by reason of one or more prior convic-
tions, unless before trial . . . the United States attorney files an
information with the court . . . stating in writing the previous convictions
to be relied upon." Here, the government filed its notice of enhancement
                         UNITED STATES v. HILL                         11
is also forced to concede that this discretionary charging decision is
reviewable when "based on a constitutionally impermissible factor
such as race, sex, or religion or motivated by animus and filed in
retaliation for the defendant’s exercise of a constitutional right." Br.
of Gov’t at 23. Accordingly, a court’s power to review the § 851
enhancement notice is entirely consistent with Bordenkircher’s
maxim that prosecutorial discretion, though broad, is not unlimited,
and courts must protect individuals from prosecutorial misconduct
whether premised on an unconstitutional motive or bad faith. See 434
U.S. at 365.

   Here, the district court concluded that the government acted with
an unconstitutional motive. Yet from the record it is unclear whether
the district court based its finding of vindictiveness on Hill’s chal-
lenge to evidence concerning the October 29 incident, or on Hill’s
exercise of his right to a trial following re-indictment. Compare J.A.
509 ("[T]he government [was] belligerent enough to . . . ask for an
enhancement . . . simply because they are ticked off at the Court
because I made an adverse evidentiary ruling for them . . . and they
are taking it out on your client . . . .") and id. at 516 ("The govern-
ment . . . sought the enhancement only after The Court’s evidentiary
ruling . . . .") with id. (stating the government filed the enhancement
notice "only as a result of the government’s frustration with the defen-
dant for continuing to exercise his right to a trial on the superseding
indictment").

   While the former ground might support a finding of vindictiveness,
see, e.g., Blackledge, 417 U.S. at 28-29; Goodwin, 457 U.S. at 373
("in certain cases in which action detrimental to the defendant has
been taken after the exercise of a legal right . . . it [is] necessary to
‘presume’ an improper vindictive motive"), the latter ground clearly
would not, see Bordenkircher, 434 U.S. at 363 (holding presumption

pursuant to 21 U.S.C. § 851 two days before Hill’s retrial, thus there is
no dispute that such filing satisfied the modest procedural requirements.
See, e.g., United States v. Rice, 43 F.3d 601, 604 (11th Cir. 1995) (hold-
ing that government’s announcement on the day that trial began, but
before jury was empaneled, that it was seeking enhancement complied
with the statutory requirement).
12                       UNITED STATES v. HILL
of vindictiveness does not arise when the government carries out a
threat, made during plea negotiations, to file additional charges
against a defendant who declines to plead guilty); United States v.
Morsley, 64 F.3d 907, 920 (4th Cir. 1995) (discussed infra). Based on
this lack of clarity,6 we must remand for the district court to conduct
plenary review of the prosecutorial vindictiveness issue. Because the
issue of whether the filing of a § 851 enhancement can constitute vin-
dictiveness is somewhat unusual, and because the government urges
us to hold, as a matter of law, that the filing of a § 851 enhancement
does not constitute vindictive prosecution, we offer some guidance.

   If the district court interpreted the filing of the § 851 enhancement
as the government’s response to the evidentiary challenge that
resulted in the exclusion of evidence at Hill’s first trial, our cases do
not expressly foreclose the possibility of a vindictiveness finding on
that basis. Contrary to the government’s suggestion, see, e.g., Br. of
Gov’t at 26 ("The government’s discretionary authority to file a Sec-
tion 851 notice is virtually absolute and unreviewable."), there is no
per se rule that the filing of a § 851 enhancement cannot amount to
vindictive prosecution. For the power of the prosecutor to penalize
egregiously and vindictively after the defendant’s exercise of a consti-
  6
    Additionally, we note that it is unclear from the record whether the
district court based its vindictive prosecution holding on the actual ani-
mus standard or upon a finding of a reasonable likelihood of vindictive-
ness. While at one point the district court remarked that the
"government’s action in seeking the sentence enhancement only on the
second trial, even though all the raw material to do so was available to
the government during the first trial, proves that the government was
motivated by animus," J.A. 516, the totality of the court’s statements, see
J.A. 509-16, and the context of the trial proceedings implicate the "rea-
sonable likelihood" standard. This conclusion is buttressed by the fact
that Defendant Hill presented no evidence of vindictive prosecution
whatsoever. Therefore, a finding of actual vindictiveness is unsupport-
able, because as we stated in Wilson, 262 F.3d at 314, to establish such
a claim "a defendant must show, through objective evidence, that (1) the
prosecutor acted with genuine animus toward the defendant and (2) the
defendant would not have been prosecuted but for that animus." Because
Hill made no showing of actual vindictiveness, we conclude that the dis-
trict court must have made its finding of vindictive prosecution based on
the reasonable likelihood standard.
                         UNITED STATES v. HILL                         13
tutional right is as powerful, if not more powerful, than his or her
power to charge in such a manner. See United States v. Cespedes, 151
F.3d 1329, 1332 (11th Cir. 1998) (noting enhancement is comparable
to prosecutor’s charging power).

    Although we have not addressed the question of whether a pre-
sumption of vindictive prosecution arises when the government files
a post-mistrial § 851 notice of enhancement when the mistrial results
from exercise of the defendant’s due process rights, we have
addressed vindictive prosecution in the more general context of § 851
notice. See Morsley, supra. In Morsley, we considered a defendant’s
claim that the government engaged in vindictive prosecution by seek-
ing an enhanced penalty following his repudiation of his plea agree-
ment. 64 F.3d at 920. In that case, the defendant contended the
government’s conduct was retaliatory and designed to punish him for
exercising his right to a jury trial. We held that Bordenkircher, 434
U.S. at 363, precluded such a claim. Morsley, 64 F.3d at 920. We rea-
soned that Bordenkircher directly controlled because the prosecutor
expressly told the defendant that if he did not plead guilty, the prose-
cutor would return to the grand jury to obtain additional charges that
would increase defendant’s punishment. See id. We stated that the
defendant "was well aware of the risk associated with denouncing his
plea agreement and proceeding to trial. He nonetheless chose to
chance the outcome of a jury trial in the hope of obtaining a better
result than what the government had offered in exchange for a guilty
plea." Id. Furthermore, we stressed that after defendant "made this
voluntary choice, the government did not reindict [defendant] on
more serious charges, but rather simply pursued the charges . . . listed
in the initial indictment with the intent of obtaining a stiffer penalty
than that originally bargained for in the plea agreement." Id. (empha-
sis added). Nowhere, however, did we exclude the possibility that the
filing of a § 851 notice may constitute vindictive prosecution outside
the context of a plea bargain.

   As discussed above, the right to due process of law is violated
where the Government increases the severity of charges in response
to the exercise of constitutional or statutory rights. In recognizing that
the fear of greater punishment may deter a person from exercising his
rights, the Supreme Court has stated that a presumption of vindictive-
14                       UNITED STATES v. HILL
ness may arise when prosecutors take actions that raise "a realistic
likelihood of ‘vindictiveness.’" Blackledge, 417 U.S. at 27.

   Post-Blackledge, however, the Supreme Court has found the pre-
sumption of vindictiveness only in cases in which the prosecutor files
more serious charges after a defendant invokes his or her post-
conviction right to appeal. See, e.g., Thigpen v. Roberts, 468 U.S. 27,
30-31 (1984); see also United States v. Perry, 335 F.3d at 324 (stating
"a presumption of prosecutorial vindictiveness is generally warranted
only in a post-conviction setting") (citing Pearce, 395 U.S. at 726).
By contrast, the Supreme Court has rejected the presumption when a
superseding indictment was filed before trial after plea bargaining dis-
cussions terminated. See Bordenkircher, supra. The Supreme Court,
however, has not reached the issue of whether a presumption of vin-
dictiveness arises when more severe charges are filed after a mistrial.
We have addressed this question in a limited fashion as have some of
our sister circuits. The fact that a mistrial has occurred unquestionably
removes the case from the rigid pre-trial plea bargain context of Bor-
denkircher, but it is also clear that post-mistrial cases are not directly
equivalent to the post-conviction setting of Blackledge.7
  7
   The Second Circuit has recognized that Blackledge-like pressures
might operate in the context of a mistrial. See United States v. Kahn, 787
F.2d 28, 32 (2d Cir. 1986). In Lane v. Lord, 815 F.2d 876, 878-79 (2d
Cir. 1987), the Second Circuit held that additional charges in a supersed-
ing indictment after mistrial did not raise the presumption of vindictive-
ness. However, the Second Circuit rested its holding that there was no
presumption of vindictiveness on the fact that although the prosecutor
added a count, the defendant was not "expose[d] to any greater criminal
penalty than the original indictment." Id. at 879. The court stated "in the
mistrial context, we believe that a threat of greater punishment is
required to justify a ‘realistic’ apprehension of the retaliatory motive on
the part of the prosecution." Id. (citing Blackledge, 417 U.S. at 27); see
also Paradise v. CCI Warden, 136 F.3d 331, 335 (2d Cir. 1998) (recog-
nizing that Lane remains good law, and reiterating the greater punish-
ment requirement). In Lane, the Second Circuit noted that in Blackledge,
the Supreme Court "emphasized that the prosecution creates an appre-
hension of vindictiveness by ‘upping the ante.’" 815 F.2d at 879 (citing
Blackledge, 417 U.S. at 27-28). The court concluded that "[i]n the
absence of a prospect of exposure to increased punishment, we do not
believe that a defendant’s right to move for a mistrial is realistically
chilled by the possibility of facing additional charges on retrial." Id.
                        UNITED STATES v. HILL                        15
   Our court and our sister circuits have held that the presumption of
vindictiveness does not generally arise in the post-mistrial context,
but all have declined to adopt a per se rule. For example, in Fiel, 35
F.3d at 1007-08, we held there was no presumption of vindictiveness
when following a mistrial due to a hung jury, the prosecutor brought
additional charges based on newly discovered evidence. We stressed
that "[w]here the change in the indictment is prompted ‘by newly dis-
covered evidence supporting the imposition of additional counts . . .
a presumption of vindictiveness is not warranted.’" Id. at 1008 (cita-
tion omitted).

   Some of our sister circuits have held that vindictive prosecution
claims do not usually arise after a mistrial because the defendant is
not affirmatively enforcing his or her constitutional rights. See, e.g.,
United States v. Morales, 108 F.3d 1213, 1220 (10th Cir. 1997) (find-
ing no presumption of vindictiveness when government lodges addi-
tional charges after mistrial); United States v. Rogers, 18 F.3d 1425,
1430 (8th Cir. 1994) (holding presumption did not arise where prose-
cutor brought additional charges in re-indictment following mistrial
due to a hung jury); United States v. Marrapese, 826 F.2d 145, 149
(1st Cir. 1987) (holding vindictiveness was not present when charges
were added post-mistrial due to hung jury).

   Indeed, United States v. Contreras, 108 F.3d 1255 (10th Cir. 1997),
is emblematic of this post-mistrial line of cases. In Contreras, the
government brought a superseding indictment with additional charges
following a mistrial due to a hung jury. After conviction on those
charges, the Tenth Circuit reviewed the district court’s denial of
defendant’s claim that the additional charges should have been dis-
missed based on prosecutorial vindictiveness. See id. at 1262. The
appeals court opined that generally following a mistrial due to hung
jury, "there is no reason why the prosecutor would consider the defen-
dant responsible for a new trial." Id. (citation omitted). Nonetheless,
the court recognized that the Supreme Court has refused to adopt per
se rules in the prosecutorial vindictiveness context, thus it was neces-
sary to "look to the totality of the objective circumstances surround-
ing the prosecutorial discretion." Id. (citation omitted).

   Here, unlike Contreras, there is at least some indication that the
district court found a reason why the prosecution considered the
16                       UNITED STATES v. HILL
defendant responsible for the new trial. See J.A. 509 (stating the gov-
ernment asked for an enhancement "simply because they are ticked
off at The Court because I made an adverse evidentiary ruling for
them and dismissed a count because they weren’t ready to go to trial
when they were scheduled to go, and they are taking it out on your
client . . . .") (emphasis added). Compare United States v. Perry, 335
F.3d at 324 ("[T]he unopposed mistrial resulting from the deadlocked
jury did not arise from [defendant’s] exercise of a protected right, but
rather was based on trial events largely beyond his control . . . .").
However, the ambiguities in the district court’s ruling from the bench
prevent us from engaging in a meaningful review of its finding of vin-
dictiveness, thus we remand so that the district court may conduct ple-
nary review of the vindictiveness issue.

                                   B.

   Moreover, under either basis for the district court’s finding of vin-
dictiveness, we must nonetheless vacate Hill’s sentence because the
district court erred in making the presumption of vindictiveness irre-
buttable. As we stated in Wilson, when a presumption of vindictive-
ness arises, the prosecution must be afforded an opportunity to rebut
that presumption. 262 F.3d at 314. See also Goodwin, 457 U.S. at 374
(stating that the government may overcome the presumption "only by
objective information in the record justifying the increased sen-
tence"). Here, after finding a presumption of vindictiveness at the sen-
tencing hearing and refusing to impose the mandatory minimum
sentence, the district judge failed to give the government an opportu-
nity to rebut the presumption. See J.A. 508-520. By making the pre-
sumption of vindictiveness irrebuttable, the district court committed
a clear legal error. Thus, on remand, in addition to clarifying its basis
for the finding of vindictiveness, the district court must give the
United States an opportunity to rebut any presumption of vindictive-
ness.

                                   V.

   For the reasons stated above, we affirm Hill’s conviction on each
of the six underlying counts of the superseding indictment. Likewise,
we affirm the district court’s application of the Sentencing Guide-
lines. However, because the district court did not clearly indicate its
                       UNITED STATES v. HILL                      17
reasoning for the finding of vindictiveness and did not give the gov-
ernment the opportunity to rebut any presumption of vindictiveness,
we vacate the district court’s sentence and remand for consideration
in light of this opinion.

                                  AFFIRMED IN PART, VACATED
                                 IN PART AND REMANDED WITH
                                               INSTRUCTIONS
