                     FOR PUBLICATION

   UNITED STATES COURT OF APPEALS
        FOR THE NINTH CIRCUIT


 UNITED STATES OF AMERICA,                    Nos.     17-10310
               Plaintiff-Appellee,                     17-10311
                                                       17-10312
                    v.
                                                     D.C. Nos.
 DAVID JAMES SAINZ,                            5:11-cr-00894-BLF-1
            Defendant-Appellant.               5:11-cr-00712-BLF-2
                                               5:11-cr-00640-BLF-3

                                                     OPINION



        Appeals from the United States District Court
            for the Northern District of California
       Beth Labson Freeman, District Judge, Presiding

         Argued and Submitted November 16, 2018
                 San Francisco, California

                     Filed August 12, 2019

  Before: A. Wallace Tashima and Milan D. Smith, Jr.,
 Circuit Judges, and Lawrence L. Piersol, * District Judge.

                    Opinion by Judge Piersol

     *
       The Honorable Lawrence L. Piersol, United States District Judge
for the District of South Dakota, sitting by designation.
2                   UNITED STATES V. SAINZ

                          SUMMARY **


                          Criminal Law

    Reversing the district court’s denial of a motion for a
sentence reduction under 18 U.S.C. § 3582(c)(2) and
remanding for further proceedings, the panel held that a
district court may not sua sponte raise a defendant’s waiver
of the right to file a § 3582(c)(2) motion and deny the motion
on that ground.


                            COUNSEL

Carman A. Smarandoiu (argued), Chief, Appellate Unit;
Steven G. Kalar, Federal Public Defender; Office of the
Federal Public Defender, San Francisco, California; for
Defendant-Appellant.

Merry J. Chan (argued), Assistant United States Attorney; J.
Douglas Wilson, Chief, Appellate Division; United States
Attorney’s Office, San Francisco, California; for Plaintiff-
Appellee.




    **
       This summary constitutes no part of the opinion of the court. It
has been prepared by court staff for the convenience of the reader.
                 UNITED STATES V. SAINZ                    3

                        OPINION

PIERSOL, District Judge:

    In this case of first impression, we consider whether a
district court may sua sponte raise a defendant’s waiver of
the right to seek relief under 18 U.S.C. § 3582(c)(2) and
deny the defendant’s motion for resentencing on that ground.
We hold that it may not. Accordingly, we reverse the district
court’s denial of David Sainz’s motion for a sentence
reduction.

I. Background

    In July 2012, Sainz pleaded guilty to six drug offenses.
Sainz’s advisory sentence range under the United States
Sentencing Guidelines was 188–235 months in prison. The
district court sentenced Sainz to 188 months in prison.

    Sainz filed a notice of appeal, but later dismissed his
appeals when he and the government entered into a post-
conviction cooperation agreement. That agreement stated
that Sainz’s sentence would be reduced if he provided
substantial assistance to the government. The agreement
contained an express waiver of Sainz’s right to seek relief
under 18 U.S.C. § 3582(c)(2).

    The government abided by its promise. It filed a motion
to reduce Sainz’s sentence under Federal Rule of Criminal
Procedure 35(b)(2), and recommended a 151-month prison
sentence. Sainz asked the court for the mandatory minimum
sentence of 120 months in prison.

    On October 21, 2014, the district court held a
resentencing hearing. Sainz raised “the prospect of [an]
additional two-point reduction for . . . the congressional
4                UNITED STATES V. SAINZ

amendment, which doesn’t take [e]ffect until Congress’s
failure to act on November 1st. Which I guess we can all
expect.” Sainz was referring to a forthcoming amendment
to USSG § 2D1.1, which would lower by two levels the base
offense level for Sainz’s convictions. Although the
amendment had not yet been enacted, the court agreed that
the amendment was likely to take effect on November 1
because “[y]ou can expect Congress to do nothing.” Sainz
and the sentencing judge then engaged in a colloquy about
whether the court could sentence Sainz below the 120-month
mandatory minimum sentence. The court concluded that
“Rule 35 opens the door to [a sentence] below the mandatory
minimum . . . . The power of the court is such that I could
reduce the sentence [below the mandatory minimum].”

    The court sentenced Sainz to 120 months in prison.
Following the imposition of the sentence, the government
asked the court whether the sentence was “in contemplation
of the expected two-level guideline reduction.” The
sentencing judge responded that he

       [had taken] that into consideration . . . I have
       taken [into] consideration the reduction that
       comes with that because of the motion made
       by the court, made and accepted by the court
       . . . [I] have before me the anticipation that
       the next week there will be a reduction of the
       sentence level . . . all of that consideration
       leads to my conclusion that a sentence of 120
       months is sufficient under the circumstances.

    In October 2015, Sainz moved for a reduction of his 120-
month sentence under 18 U.S.C. § 3582(c)(2), which allows
resentencing for “a defendant who has been sentenced to a
term of imprisonment based on a sentencing range that has
                   UNITED STATES V. SAINZ                        5

subsequently been lowered.” Under Amendment 782,
Sainz’s Guidelines range had been reduced from 188–235
months in prison to 151–188 months in prison.

    The district court 1 denied Sainz’s motion. The court
based its holding on the fact that “Sainz expressly waived
the right to seek relief under 18 U.S.C. § 3582,” even though
neither party had raised the waiver. The court also declined
to consider a reduction to Sainz’s sentence sua sponte on the
ground that “[the district court] expressly considered the
potential effect of then-expected Amendment 782 in
determining the appropriate sentence reduction for Sainz’s
cooperation.”

II. Standard of Review

    This Court reviews for abuse of discretion a district
court’s decision to grant or deny a sentence reduction under
18 U.S.C. § 3582(c)(2). United States v. Dunn, 728 F.3d
1151, 1155 (9th Cir. 2013). “A district court may abuse its
discretion if it does not apply the correct law or if it rests its
decision on a clearly erroneous finding of material fact.” Id.
(quoting United States v. Lightfoot, 626 F.3d 1092, 1094 (9th
Cir. 2010)). Whether a district court may sua sponte raise a
defendant's waiver of the right to seek relief under 18 U.S.C.
§ 3582(c)(2) is a legal question, which we review de novo.
See United States v. Chaney, 581 F.3d 1123, 1125 (9th Cir.
2009) (questions of law underlying a district court’s denial
of a motion under 18 U.S.C. § 3582(c)(2) are reviewed de
novo).


    1
       Judge D. Lowell Jensen, who originally sentenced Sainz in
October 2014, retired from the bench in November 2014. Accordingly,
the case was reassigned to Judge Beth Labson Freeman.
6                UNITED STATES V. SAINZ

III.   Discussion

    We begin our analysis by noting that no circuit has
directly addressed whether it is appropriate for a district
court to invoke sua sponte a defendant’s waiver in an
agreement with the government of the right to file a
§ 3582(c)(2) motion. Indeed, the government does not cite
a single case in which a district court sua sponte raised the
defendant’s waiver of such a right after the government
failed to raise it.

    Although we have not addressed whether a district court
may raise a defendant’s waiver, we have concluded that, on
appeal, courts should not raise waiver sua sponte. If the
government does not raise the argument in the district court
that a defendant has waived the right to bring a § 3582(c)(2)
motion in a plea agreement, we have held that the
government has waived the right to make this argument on
appeal. We addressed the issue tangentially in United States
v. Chaney, 581 F.3d 1123 (9th Cir. 2009). In Chaney, the
defendant sought a sentence reduction under § 3582(c)(2).
The district court denied the § 3582(c)(2) motion on the
merits. See id. at 1125. In her plea agreement, the defendant
had waived her rights “to appeal any aspect of her sentence
as long as her sentence is no longer than the top of the
sentencing guidelines range” and “to bring a post-conviction
attack on her . . . sentence.” Id. at 1124 n.1. Because the
government had not sought to enforce the defendant’s
agreement not to seek a sentence reduction in the district
court, we expressly declined to address whether the
defendant waived her right to file the § 3582(c)(2) motion or
to appeal from its denial. See id.

   We also declined to raise a waiver sua sponte in
Norwood v. Vance, 591 F.3d 1062 (9th Cir. 2010). There,
we held that, even though the defendants may have waived
                   UNITED STATES V. SAINZ                       7

the issue of whether they were entitled to qualified immunity
by failing to raise the issue in the district court, the plaintiff
waived the waiver because he failed to raise it on appeal and
instead addressed qualified immunity on the merits. See id.
at 1068 (“[We] will not address waiver if not raised by the
opposing party.”). We addressed defendants’ qualified
immunity defense on the merits and concluded they were
entitled to qualified immunity. Id. at 1070. The holding in
Norwood on waiver was not unequivocal, however, because
we also noted that even if we had discretion to sua sponte
enforce the waiver, we would choose not to do so because
“the more prudent course is to resolve the case on the basis
of the issues actually briefed and argued by the parties.” Id.
at 1068.

    The government, relying on two habeas cases, contends
that the district court was permitted to sua sponte raise
Sainz’s waiver because the government was silent about the
waiver and, therefore, its waiver was not shown to be
intentional. See Day v. McDonough, 547 U.S. 198 (2006),
and Wood v. Milyard, 566 U.S. 463 (2012). We conclude
that neither case supports the government’s argument.

    In Day, which the government relied on for the first time
at oral argument, the Supreme Court held that a district court
had the authority to raise sua sponte the § 2244(d) statute of
limitations defense and dismiss the petition as untimely even
though the State’s answer had expressly conceded the
timeliness of the petition. 547 U.S. at 202. Because
§ 2244(d) is not jurisdictional, “courts are under no
obligation to raise the time bar sua sponte.” Id. at 205
(emphasis omitted). But the Court held that “the limitations
defense resembles other threshold barriers—exhaustion of
state remedies, procedural default, nonretroactivity—courts
have typed ‘nonjurisdictional,’ although recognizing that
8                    UNITED STATES V. SAINZ

those defenses ‘implicat[e] values beyond the concerns of
the parties.’” Id. (quoting Acosta v. Artuz, 221 F.3d 117, 123
(2d Cir. 2000)). “The considerations of comity, finality, and
the expeditious handling of habeas proceedings that
motivated AEDPA . . . counsel against an excessively rigid
or formal approach to the affirmative defenses now listed in
Habeas Rule 5.” Id. at 208 (citing Granberry v. Greer, 481
U.S. 129, 131–34 (1987)). The Court recognized that “it
would make scant sense to distinguish in this regard
AEDPA’s time bar from other threshold constraints on
federal habeas petitioners.” Id. at 209. The Court also
stated, however, that “should a State intelligently choose to
waive a statute of limitations defense, a district court would
not be at liberty to disregard that choice,” id. at 210 n.11, as
it would be “an abuse of discretion to override a State’s
deliberate waiver of a limitations defense,” id. at 202.

    The Court in Day concluded that the State’s concession
that the habeas petition was timely was a mistake that was
patent on the face of the State’s filings; the district court had
“confronted no intelligent waiver on the State’s part, only an
evident miscalculation of the elapsed time under a statute
designed to impose a tight time constraint on federal habeas
petitioners.” Id. at 202; see also id. at 203 (explaining that
the State had miscalculated the deadline by “[o]verlooking
controlling Eleventh Circuit precedent”).            There was
“nothing in the record suggest[ing] that the State
‘strategically’ withheld the defense or chose to relinquish it.”
Id. at 211. Accordingly, the Court held that the district court
had the discretion to raise the issue. 2


    2
      But “before acting on its own initiative, a court must accord the
parties fair notice and an opportunity to present their positions,” it must
“assure itself that the petitioner is not significantly prejudiced by the
                     UNITED STATES V. SAINZ                              9

     Day does not support the weight that the government
puts on it. The State in Day made a mistake in calculating
the tolled time for the statute of limitations, and the district
court confronted a petition that was obviously untimely.
Here, the government never claimed in its appellate brief that
it inadvertently failed to invoke Sainz’s waiver, and there is
no obvious mistake about the waiver as there was in the
State’s calculation of the tolled time in Day. Instead, the
government omitted an argument based on facts of which it
was well aware: Sainz had waived his right to file a
§ 3582(c)(2) motion as part of the post-conviction
cooperation agreement that the government entered into with
him. Nevertheless, the government never relied on that
waiver when addressing the § 3582(c)(2) motion before the
district court. Furthermore, the policy concerns surrounding
§ 2254 habeas petitions and the rules that favor allowing the
district court to raise the timeliness of a habeas petition sua
sponte are not present in this case. For these reasons we find
that Day is not applicable to this case.

    Wood also is not persuasive authority for the
government’s position. In Wood, the movant filed a § 2254
habeas petition that was arguably untimely. Wood, 566 U.S.
at 474. The State told the district court that it would not
challenge the timeliness of the petition and the district court
addressed the petition on the merits. Id. The Supreme Court

delayed focus on the limitation issue,” and it must “determine whether
the interests of justice would be better served by addressing the merits or
by dismissing the petition as time barred.” Id. at 210 (quoting Granberry,
481 U.S. at 136) (other citations and quotations omitted). Here, Sainz
was not given notice and an opportunity to address waiver, he was
prejudiced when his motion for a sentence reduction was denied based
on the waiver, and the record shows that the government waived the
waiver. These considerations support our conclusion that the district
court should not have sua sponte raised Sainz’s waiver.
10                UNITED STATES V. SAINZ

ruled that, given that the State deliberately waived its
challenge to the timeliness of the petition, the Tenth Circuit
abused its discretion by ignoring the district court’s review
of the merits of Wood’s petition and sua sponte dismissing
the petition on statute of limitations grounds. Id. (noting that
“the State . . . deliberately steered the District Court away
from the question and towards the merits of Wood’s
petition”).

    The government argues that, in contrast to Wood, there
is no evidence it intentionally refrained from invoking
Sainz’s waiver of his right to file a § 3582(c)(2) motion, and
thus the district court properly denied the motion by sua
sponte raising Sainz’s waiver.

    But the situation here differs from Wood.              The
government’s silence about Sainz’s waiver did not lead the
district court to ask if the government wished to intentionally
relinquish or abandon the defense, and the government did
not expressly disavow the waiver. The government has not
pointed to any evidence in the record that it inadvertently
failed to raise Sainz’s waiver below. We decline to hold that
the government’s silence about a defendant’s waiver of the
right to file a § 3582(c)(2) motion allows the district court to
sua sponte raise the waiver.

     Indeed, we have held that the government can waive
waiver by failing to assert it. United States v. Tercero, 734
F.3d 979, 981 (9th Cir. 2013) (“It is well-established that the
government can waive waiver implicitly by failing to assert
it.”) (quoting Norwood, 591 F.3d at 1068). In other words,
the government must do more than remain silent; it must
expressly invoke the waiver to avoid waiving it.
Accordingly, because the Day and Wood habeas cases do not
control the outcome here, under our law and the
circumstances in this case, it would be an abuse of discretion
                  UNITED STATES V. SAINZ                    11

for the court to conclude that the government’s silence and
failure to invoke the waiver of the right to file the
§ 3582(c)(2) motion allows the district court to raise the
waiver on its own volition.

     We are also persuaded by the reasoning of several
circuits that have declined to raise sua sponte a defendant’s
waiver of his right to appeal his sentence if the government
did not raise the issue. The Tenth Circuit has recognized that
the obligation to raise a waiver of a right to appeal rests
solely with the government; if the government does not raise
the issue, it is forfeited. See United States v. Calderon, 428
F.3d 928 (10th Cir. 2005). The Tenth Circuit explained that
one of the reasons for this result, “rooted in the adversarial
character of litigation,” is that in some cases “the
government might conclude that justice would be better
served by allowing a criminal defendant to appeal a
wrongful sentence, even when the plea agreement included
an appeal waiver.” Calderon, 428 F.3d at 931. Likewise, in
United States v. Garner, 519 F.App’x 823 (4th Cir. 2013),
the Fourth Circuit stated its policy not to sua sponte raise a
defendant’s waiver of his right to appeal. See id. at 825
(citing United States v. Poindexter, 492 F.3d 263, 271 (4th
Cir. 2007); United States v. Blick, 408 F.3d 162, 168 (4th
Cir. 2005)).

    Sainz relies heavily on Burgess v. United States, 874
F.3d 1292 (11th Cir. 2017), where the defendant expressly
waived his right to bring a § 2255 motion as part of his plea
agreement and, after he filed a § 2255 motion, the
government did not argue that the defendant had waived this
right. The district court, sua sponte and without notice to the
parties, denied one of the § 2255 claims based on the waiver,
even though the government did not invoke it. Id. at 1294–
95. The Eleventh Circuit reversed, holding that the rules
12                UNITED STATES V. SAINZ

applicable to civil cases rather than the reasoning of Day and
Wood apply to a waiver of the right to file a § 2255 motion.
See id. at 1299. Those rules require the parties to assert
affirmative defenses. See id. at 1296–97. The Eleventh
Circuit distinguished the concerns underlying a district
court’s sua sponte raising a habeas procedural defense such
as timeliness in Day and Wood from a district court’s
invocation of a collateral-action waiver in a privately
negotiated plea agreement.

    First, the latter “does not reflect an institutionally
determined judgment that concerns of finality and judicial
economy generally outweigh the interest of ensuring that a
defendant has been convicted and sentenced within the
bounds of the law.” Id. at 1299. Second, allowing courts
sua sponte to invoke collateral-attack waivers contravenes
“the usual rule in our party-presentation system,” which
“requires the parties to invoke their own claims and
defenses.” Id. at 1300. “If a court engages in what may be
perceived as the bidding of one party by raising claims or
defenses on its behalf, the court may cease to appear as a
neutral arbiter, and that could be damaging to our system of
justice.” Id. Third, “the neutral-arbiter concern is particularly
apt when the court invokes an affirmative defense on behalf
of the government, where the only source of the defense
stems from the plea agreement.” Id. The Eleventh Circuit
noted that the integrity of the courts could be impaired if they
invoke the benefits of plea agreements on behalf of the
government when Federal Rule of Criminal Procedure
11(c)(1) prohibits courts from participating in plea-
negotiations in the first instance.

    Applying the Civil Rules, the Eleventh Circuit held that
the government must expressly invoke a § 2255 waiver;
otherwise, the district court may not invoke it. See id. at
                  UNITED STATES V. SAINZ                   13

1301. The court may, however, ask the government whether
it intends to rely on the waiver and entertain a motion to
amend the pleadings by the government if its initial response
failed to invoke the waiver. Id.

     Although § 3582(c)(2) proceedings, unlike § 2255
proceedings, are deemed criminal in nature, see United
States v. Ono, 72 F.3d 101, 102 (9th Cir. 1995), we conclude
that the Eleventh Circuit’s analysis in Burgess is persuasive.
We thus apply the same principles to the government’s
failure to raise a § 3582(c)(2) waiver and hold that district
courts are not allowed to raise the waiver sua sponte. Just as
a party may waive a contract provision that is beneficial to
it, the government may waive a beneficial provision in a plea
agreement. When the district court raises the issue sua
sponte, it risks becoming an advocate for the government,
undermining the principle of party presentation. As the
Supreme Court has reasoned:

       [Courts] do not, or should not, sally forth
       each day looking for wrongs to right. We
       wait for cases to come to us, and when they
       do we normally decide only questions
       presented by the parties. Counsel almost
       always know a great deal more about their
       cases than we do, and this must be
       particularly true of counsel for the United
       States, the richest, most powerful, and best
       represented litigant to appear before us.

Greenlaw v. United States, 554 U.S. 237, 244 (2008)
(quoting United States v. Samuels, 808 F.2d 1298, 1301 (8th
Cir. 1987) (R. Arnold, J., concurring in denial of reh’g en
banc)). The better method, consistent with our system of
party presentation, is to entrust to counsel for the
14                      UNITED STATES V. SAINZ

government the decision whether to enforce the waiver of a
right to file a § 3582(c)(2) motion for a sentence reduction.

    Here, the United States was represented by an Assistant
United States Attorney who undoubtedly was familiar with
the record and Sainz’s waiver of his right to file a
§ 3582(c)(2) motion, a term the government negotiated for
as part of the post-conviction cooperation agreement. There
could be many reasons why the government did not raise the
issue of waiver in the district court even though it had
bargained for the waiver. 3 “But as a general rule, our
adversary system is designed around the premise that the
parties know what is best for them, and are responsible for
advancing the facts and arguments entitling them to relief.”
Greenlaw, 554 U.S. at 244 (quoting Castro v. United States,
540 U.S. 375, 386 (2003)) (internal quotation marks
omitted) (Scalia, J., concurring in part and concurring in
judgment). “The rule that points not argued will not be
considered is more than just a prudential rule of
convenience; its observance, at least in the vast majority of
cases, distinguishes our adversary system of justice from the
inquisitorial one.” United States v. Burke, 504 U.S. 229, 246

     3
         In his opening brief, Sainz’s counsel stated:

            The government’s approach in Mr. Sainz’s case is
            consistent with its approach throughout litigation of
            sentence reduction motions under Amendment 782 in
            the Northern District of California. To undersigned
            counsel’s knowledge, the government did not invoke
            the § 3582(c)(2) waivers in any of the many cases
            where such waivers existed and indeed the parties
            proceeded via stipulation in the vast majority of those
            cases.

The government did not deny or otherwise respond to this representation
in its appellate brief.
                  UNITED STATES V. SAINZ                      15

(1992), superseded by statute on other grounds, (Scalia, J.,
concurring). Accordingly, when the government fails to
raise waiver in the district court and chooses to litigate a
§ 3582(c)(2) motion on the merits, the district court abuses
its discretion if it raises the defendant’s waiver sua sponte.

IV.     Conclusion

    Because the government waived Sainz’s waiver of his
right to file a § 3582(c)(2) motion by failing to raise it in the
district court, the district court abused its discretion by
raising the waiver sua sponte. Therefore, we reverse the
district court’s denial of the § 3582(c)(2) motion on waiver
grounds and remand this case to the district court for further
proceedings consistent with this opinion.

      REVERSED AND REMANDED.
