OPINION OF THE COURT
[562 U.S. 480]
Justice Sotomayordelivered the opinion of the Court.
This Court has long recognized that sentencing judges “exercise a wide discretion” in the types of evidence they may consider when imposing sentence and that “ [h] ighly relevant—if not essential—to [the] selection of an appropriate sentence is the possession of the fullest information possible concerning the defendant’s life and characteristics.” Williams v. New York, 337 U.S. 241, 246-247, 69 S. Ct. 1079, 93 L. Ed. 1337 (1949). Congress codified this principle at 18 U.S.C. § 3661, which provides that “[n]o limitation shall be placed on the information” a sentencing court may consider “concerning the [defendant’s] background, character, and conduct,” and at § 3553(a), which sets forth certain factors that sentencing courts must consider, including “the history and characteristics of the defendant,” § 3553(a)(1). The United States Court of Appeals for the Eighth Circuit concluded in this case that the District Court, when resentencing petitioner *208after his initial sentence had been set aside on appeal, could not consider evidence of petitioner’s rehabilitation since his initial sentencing. That conclusion conflicts with longstanding principles of federal sentencing law and Congress’ express directives in §§ 3661 and 3553(a). Although a separate statutory provision, § 3742(g)(2), prohibits a district court at resentencing from imposing a sentence outside the Federal Sentencing Guidelines range except upon a ground it relied upon at the prior sentencing—thus effectively precluding the court from considering post-sentencing rehabilitation for purposes of imposing
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a non-Guidelines sentence—that provision did not survive our holding in United States v. Booker, 543 U.S. 220, 125 S. Ct. 738, 160 L. Ed. 2d 621 (2005), and we expressly invalidate it today.
We hold that when a defendant’s sentence has been set aside on appeal, a district court at resentencing may consider evidence of the defendant’s postsentencing rehabilitation and that such evidence may, in appropriate cases, support a downward variance from the now-advisory Federal Sentencing Guidelines range. Separately, we affirm the Court of Appeals’ ruling that the law of the case doctrine did not require the District Court in this case to apply the same percentage departure from the Guidelines range for substantial assistance that had been applied at petitioner’s prior sentencing.
I
In October 2003, petitioner Jason Pepper was arrested and charged with conspiracy to distribute 500 grams or more of methamphetamine in violation of 21 U.S.C. § 846. After pleading guilty, Pepper appeared for sentencing before then-Chief Judge Mark W. Bennett of the U. S. District Court for the Northern District of Iowa. Pepper’s sentencing range under the Guidelines was 97 to 121 months.1 The Government moved for a downward departure pursuant to USSG § 5K1.1 based on Pepper’s substantial assistance and recommended a 15-percent downward departure.2 The District Court, however, sentenced Pepper to a 24-month prison
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term, resulting in an approximately 75-percent downward departure from the low end of the Guidelines range, to be followed by five years of supervised release. The Government appealed Pepper’s sentence, and in June 2005, the Court of Appeals for the Eighth Circuit reversed and remanded for resentencing in light of our intervening decision in Booker (and for another reason not relevant here). See United States v. Pepper, 412 F.3d 995, 999 (Pepper I). Pepper completed his 24-month sentence three days after Pepper I was issued and began serving his term of supervised release.
*209In May 2006, the District Court conducted a resentencing hearing and heard from three witnesses. In his testimony, Pepper first recounted that while he had previously been a drug addict, he successfully completed a 500-hour drug treatment program while in prison and he no longer used any drugs. App. 104-105. Pepper then explained that since his release from prison, he had enrolled at a local community college as a full-time student and had earned As in all of his classes in the prior semester. Id., at 106-107. Pepper also testified that he had obtained employment within a few weeks after being released from custody and was continuing to work part time while attending school. Id., at 106-110. Pepper confirmed that he was in compliance with all the conditions of his supervised release and described his changed attitude since his arrest. See id., at 111 (“[M]y life was basically headed to either where—I guess where I ended up, in prison, or death. Now I have some optimism about my life, about what I can do with my life. I’m glad that I got this chance to try again I guess you could say at a decent life. . . . My life was going nowhere before, and I think that it’s going somewhere now”).
Pepper’s father testified that he had virtually no contact with Pepper during the 5-year period leading up to his arrest. Id., at 117. Pepper’s drug treatment program, according to his father, “truly sobered him up” and “made his
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way of thinking change.” Id., at 121. He explained that Pepper was now “much more mature” and “serious in terms of planning for the future,” id., at 119, and that as a consequence, he had reestablished a relationship with his son, id., at 118-119.
Finally, Pepper’s probation officer testified that, in his view, a 24-month sentence would be reasonable in light of Pepper’s substantial assistance, postsentencing rehabilitation, and demonstrated low risk of recidivism. Id., at 126-131. The probation officer also prepared a sentencing memorandum that further set forth the reasons supporting his recommendation for a 24-month sentence.
The District Court adopted as its findings of fact the testimony of the three witnesses and the probation officer’s sentencing memorandum. The court granted a 40-percent downward departure based on Pepper’s substantial assistance, reducing the bottom of the Guidelines range from 97 to 58 months. The court then granted a further 59-percent downward variance based on, inter alia, Pepper’s rehabilitation since his initial sentencing. Id., at 143-148.3 The court sentenced Pepper to 24 months of imprisonment, concluding that “it would [not] advance any purpose of federal sentencing policy or any other policy behind the federal sentencing guidelines to send this defendant back to prison.” Id., at 149-150.
The Government again appealed Pepper’s sentence, and the Court of Appeals again reversed and remanded for resentencing. See United States v. Pepper, 486 F.3d 408, 410, 413 (CA8 2007) (Pepper II). The court concluded that, while it was “a close call, [it could not] say the district court abused its discretion” by grant*210ing the 40-percent downward departure for substantial assistance. Id., at 411. The court found the further 59-percent downward variance, however,
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to be an abuse of discretion. Id., at 412-413. In doing so, the court held that Pepper’s “post-sentencing rehabilitation was an impermissible factor to consider in granting a downward variance.” Id., at 413. The court stated that evidence of postsentenc-ing rehabilitation “ ‘is not relevant and will not be permitted at resen-tencing because the district court could not have considered that evidence at the time of the original sentencing,’ ” and permitting courts to consider postsentencing rehabilitation at resentencing “would create unwarranted sentencing disparities and inject blatant inequities into the sentencing process.” Ibid.4 The Court of Appeals directed that the case be assigned to a different district judge for resentencing. Ibid.
After the Court of Appeals’ mandate issued, Pepper’s case was reassigned on remand to Chief Judge Linda R. Reade. In July 2007, Chief Judge Reade issued an order on the scope of the remand from Pepper II, stating that “ [t]he court will not consider itself bound to reduce [Pepper’s] advisory Sentencing Guidelines range by 40% pursuant to USSG § 5K1.1.” United States v. Pepper, No. 03-CR-4113-LRR, 2007 WL 2076041, *4 (ND Iowa). In the meantime, Pepper petitioned this Court for a writ of certio-rari, and in January 2008, we granted the petition, vacated the judgment in Pepper II, and remanded the case to the Court of Appeals for further consideration in light of Gall v. United. States, 552 U.S. 38, 128 S. Ct. 586, 169 L. Ed. 2d 445 (2007). See Pepper v. United States, 552 U.S. 1089, 128 S. Ct. 871, 169 L. Ed. 2d 715 (2008).
On remand, the Court of Appeals held that Gall did not alter its prior conclusion that “post-sentence rehabilitation is an impermissible factor to consider in granting a downward
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variance.” 518 F.3d 949, 953 (CA8 2008) (Pepper III). The court again reversed the sentence and remanded for resentencing.
In October 2008, Chief Judge Reade convened Pepper’s second resentenc-ing hearing. Pepper informed the court that he was still attending school and was now working as a supervisor for the night crew at a warehouse retailer, where he was recently selected by management as “associate of the year” and was likely to be promoted the following January. App. 320, 323. Pepper also stated that he had recently married and was now supporting his wife and her daughter. Id., at 321. Pepper’s father reiterated that Pepper was moving forward in both his career and his family life and that he remained in close touch with his son. See id., at 300-304.
In December 2008, Chief Judge Reade issued a sentencing memorandum. Noting that the remand language of Pepper III was nearly identical to the language in Pepper II, the court again observed that it was “not bound to reduce [Pepper’s] advisory Sentencing Guidelines range by 40%” for substantial assistance and concluded that Pepper was entitled only to a 20-percent downward departure *211because the assistance was “timely, helpful and important” but “in no way extraordinary” Sealed Sentencing Memorandum in No. 03-CR-4113-LRR (ND Iowa), Record, Doc. 198, pp. 7, 10. The court also rejected Pepper’s request for a downward variance based on, inter alia, his postsentenc-ing rehabilitation. Id., at 16.
The District Court reconvened Pepper’s resentencing hearing in January 2009. The court’s decision to grant a 20-percent downward departure for substantial assistance resulted in an advisory Guidelines range of 77 to 97 months. The court also granted the Government’s motion under Rule 35(b) of the Federal Rules of Criminal Procedure to account for investigative assistance Pepper provided after he was
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initially sentenced. The court imposed a 65-month term of imprisonment, to be followed by 12 months of supervised release.5
The Court of Appeals affirmed Pepper’s 65-month sentence. 570 F.3d 958 (CA8 2009) (Pepper IV). As relevant here, the Court of Appeals rejected Pepper’s argument that the District Court erred in refusing to consider his postsentencing rehabilitation. The court acknowledged that “Pepper made significant progress during and following his initial period of imprisonment” and “commend [ed] Pepper on the positive changes he has made in his life,” but concluded that Pepper’s argument was foreclosed by Circuit precedent holding that “post-sentencing rehabilitation is not a permissible factor to consider in granting a downward variance.” Id., at 964-965 (citing United States v. Jenners, 473 F.3d 894, 899 (CA8 2007); United States v. McMannus, 496 F.3d 846, 852, n. 4 (CA8 2007)).
The Court of Appeals also rejected Pepper’s claim that the scope of the remand and the law of the case from Pepper II and Pepper III required the District Court to reduce the applicable Guidelines range by at least 40 percent pursuant to USSG § 5K1.1. The court noted that its remand orders in Pepper II and Pepper III were “general remand [s] for resentencing,” which “did not place any limitations on the discretion of the newly assigned district court judge in resen-tencing.” 570 F.3d, at 963. The court further noted that, although issues decided by an appellate court become law of the case on remand to the sentencing court, its earlier decisions merely held that a 40-percent downward departure for substantial assistance was not an abuse of discretion, not that the District Court would be bound by the 40-percent departure previously granted. Id., at 963-964.
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We granted Pepper’s petition for a writ of certiorari, 561 U.S. 1024, 130 S. Ct. 3499, 177 L. Ed. 2d 1089 (2010), to decide two questions: (1) whether a district court, after a defendant’s sentence has been set aside on appeal, may consider evidence of a defendant’s postsentencing rehabilitation to support a downward variance when resentencing the defendant, a question that has divided the Courts of Appeals;6 and (2) whether the resen-tencing court was required, under the law of the case doctrine, to apply the *212same percentage departure from the Guidelines range for substantial assistance that had been applied at Pepper’s prior sentencing. Because the United States has confessed error in the Court of Appeals’ ruling on the first question, we appointed an am-icus curiae to defend the Court of Appeals’ judgment.7 We now vacate the Eighth Circuit’s ruling on the first question and affirm its ruling on the second.
II
A
“It has been uniform and constant in the federal judicial tradition for the sentencing judge to consider every convicted person as an individual and every case as a unique study in the human failings that sometimes mitigate, sometimes magnify, the crime and the punishment to ensue.” Koon v. United States, 518 U.S. 81, 113, 116 S. Ct. 2035, 135 L. Ed. 2d 392 (1996). Underlying this tradition is the principle that “the punishment should
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fit the offender and not merely the crime.” Williams, 337 U.S., at 247, 69 S. Ct. 1079, 93 L. Ed. 1337; see also Pennsylvania ex rel. Sullivan v. Ashe, 302 U.S. 51, 55, 58 S. Ct. 59, 82 L. Ed. 43 (1937) (“For the determination of sentences, justice generally requires consideration of more than the particular acts by which the crime was committed and that there be taken into account the circumstances of the offense together with the character and propensities of the offender”).
Consistent with this principle, we have observed that “both before and since the American colonies became a nation, courts in this country and in England practiced a policy under which a sentencing judge could exercise a wide discretion in the sources and types of evidence used to assist him in determining the kind and extent of punishment to be imposed within limits fixed by law.” Williams, 337 U.S., at 246, 69 S. Ct. 1079, 93 L. Ed. 1337. In particular, we have emphasized that “[h]ighly relevant—if not essential—to [the] selection of an appropriate sentence is the possession of the fullest information possible concerning the defendant’s life and characteristics.” Id., at 247, 69 S. Ct. 1079, 93 L. Ed. 1337. Permitting sentencing courts to consider the widest possible breadth of information about a defendant “ensures that the punishment will suit not merely the offense but the individual defendant.” Wasman v. United States, 468 U.S. 559, 564, 104 S. Ct. 3217, 82 L. Ed. 2d 424 (1984).
In 1970, Congress codified the “longstanding principle that sentencing courts have broad discretion to consider various kinds of information” at 18 U.S.C. § 3577 (1970 ed.). United States v. Watts, 519 U.S. 148, 151, 117 S. Ct. 633, 136 L. Ed. 2d 554 (1997) (per curiam). Section 3577 provided:
“No limitation shall be placed on the information concerning the background, character, and conduct of a person convicted of an offense *213which a court of the United States may receive and consider for the purpose of imposing an appropriate sentence.” (Emphasis added.)
In the Sentencing Reform Act of 1984 (SRA), 18 U.S.C. § 3551 et seq., Congress effected fundamental changes to
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federal sentencing by creating the Federal Sentencing Commission and introducing the Guidelines scheme. In doing so, however, Congress recodi-fied § 3577 without change at § 3661. The Sentencing Commission, moreover, expressly incorporated § 3661 in the Guidelines:
“In determining the sentence to impose within the guideline range, or whether a departure from the guidelines is warranted, the court may consider, without limitation, any information concerning the background, character and conduct of the defendant, unless otherwise prohibited by law. See 18 U.S.C. § 3661.” USSG § 1B1.4 (Nov. 2010) (emphasis added).
Both Congress and the Sentencing Commission thus expressly preserved the traditional discretion of sentencing courts to “conduct an inquiry broad in scope, largely unlimited either as to the kind of information [they] may consider, or the source from which it may come.” United States v. Tucker, 404 U.S. 443, 446, 92 S. Ct. 589, 30 L. Ed. 2d 592 (1972).8
The SRA did constrain sentencing courts’ discretion in important respects, most notably by making the Guidelines mandatory, see 18 U.S.C. § 3553(b)(1) (2000 ed., Supp. IV), and by specifying various factors that courts must consider in exercising their discretion, see § 3553(a). In our seminal decision in Booker, we held that where facts found by a judge by a preponderance of the evidence increased the applicable Guidelines range, treating the Guidelines as mandatory in those circumstances violated the Sixth Amendment right of criminal defendants to be tried by a jury and to have every element of an offense proved by the Government beyond a reasonable doubt. 543 U.S., at 243-244, 125 S. Ct. 738, 160 L. Ed. 2d 621. Our remedial opinion in Booker invalidated two offending provisions in the
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SRA, see id-., at 245, 125 S. Ct. 738, 160 L. Ed. 2d 621 (invalidating 18 U.S.C. §§ 3553(b)(1), 3742(e)), and instructed the district courts to treat the Guidelines as “effectively advisory,” 543 U.S., at 245, 125 S. Ct. 738, 160 L. Ed. 2d 621.
Our post-Booker opinions make clear that, although a sentencing court must “give respectful consideration to the Guidelines, Booker permits the court to tailor the sentence in light of other statutory concerns as well.” Kimbrough v. United States, 552 U.S. 85, 101, 128 S. Ct. 558, 169 L. Ed. 2d 481 (2007) (internal quotation marks and citation omitted). Accordingly, although the “Guidelines should be the starting point and the initial benchmark,” district courts may impose sentences within statutory limits based on appropriate consideration of all of the factors listed in § 3553(a), subject to appellate review for “reasonableness.” Gall, 552 U.S., at 49-51, 128 S. Ct. 586, 169 L. Ed. 2d 445. This sentencing framework applies both at a defendant’s initial sentencing and at any subsequent resen-tencing after a sentence has been set *214aside on appeal. See 18 U.S.C. § 3742(g) (“A district court to which a case is remanded . . . shall resentence a defendant in accordance with section 3553”); see also Dillon v. United States, 560 U.S. 817, 828, 827, 130 S. Ct. 2683, 177 L. Ed. 2d 271 (2010) (distinguishing between “sentence-modification proceedings” under 18 U.S.C. § 3582(c)(2), which “do not implicate the interests identified in Booker,” and “plenary resentencing proceedings,” which do).
B
In light of the federal sentencing framework described above, we think it clear that when a defendant’s sentence has been set aside on appeal and his case remanded for resentenc-ing, a district court may consider evidence of a defendant’s rehabilitation since his prior sentencing and that such evidence may, in appropriate cases, support a downward variance from the advisory Guidelines range.
Preliminarily, Congress could not have been clearer in directing that “[n]o limitation ... be placed on the information concerning the background, character, and conduct” of a defendant that a district court may “receive and consider
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for the purpose of imposing an appropriate sentence.” 18 U.S.C. § 3661. The plain language of § 3661 makes no distinction between a defendant’s initial sentencing and a subsequent resentencing after a prior sentence has been set aside on appeal. We have recognized that “the broad language of § 3661” does not provide “any basis for the courts to invent a blanket prohibition against considering certain types of evidence at sentencing.” Watts, 519 U.S., at 152, 117 S. Ct. 633, 136 L. Ed. 2d 554. A categorical bar on the consideration of postsentencing rehabilitation evidence would directly contravene Congress’ expressed intent in § 3661.
In addition, evidence of post-sentencing rehabilitation may be highly relevant to several of the § 3553(a) factors that Congress has expressly instructed district courts to consider at sentencing. For example, evidence of postsentencing rehabilitation may plainly be relevant to “the history and characteristics of the defendant.” § 3553(a)(1). Such evidence may also be pertinent to “the need for the sentence imposed” to serve the general purposes of sentencing set forth in § 3553(a)(2)—in particular, to “afford adequate deterrence to criminal conduct,” “protect the public from further crimes of the defendant,” and “provide the defendant with needed educational or vocational training ... or other correctional treatment in the most effective manner.” §§ 3553(a)(2)(B)-(D); see McMannus, 496 F.3d, at 853 (Melloy, J., concurring) (“In assessing . . . deterrence, protection of the public and rehabilitation, 18 U.S.C. § 3553(a)(2)(B)(C) & (D), there would seem to be no better evidence than a defendant’s post-incarceration conduct”). Postsentencing rehabilitation may also critically inform a sentencing judge’s overarching duty under § 3553(a) to “impose a sentence sufficient, but not greater than necessary,” to comply with the sentencing purposes set forth in § 3553(a)(2).
As the original sentencing judge recognized, the extensive evidence of Pepper’s rehabilitation since his initial sentencing is clearly relevant to the selection of an appropriate sentence
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in this case. Most fundamentally, evidence of Pepper’s conduct since his release from custody in June 2005 provides the most up-to-date picture of Pepper’s “history and charac*215teristics.” § 3553(a)(1); see United States v. Bryson, 229 F.3d 425, 426 (CA2 2000) (per curiam) ( “[A] court’s duty is always to sentence the defendant as he stands before the court on the day of sentencing”). At the time of his initial sentencing in 2004, Pepper was a 25-year-old drug addict who was unemployed, estranged from his family, and had recently sold drugs as part of a methamphetamine conspiracy By the time of his second resentencing in 2009, Pepper had been drug free for nearly five years, had attended college and achieved high grades, was a top employee at his job slated for a promotion, had reestablished a relationship with his father, and was married and supporting his wife’s daughter. There is no question that this evidence of Pepper’s conduct since his initial sentencing constitutes a critical part of the “history and characteristics” of a defendant that Congress intended sentencing courts to consider. § 3553(a).
Pepper’s postsentencing conduct also sheds light on the likelihood that he will engage in future criminal conduct, a central factor that district courts must assess when imposing sentence. See §§ 3553(a)(2)(B)-(C); Gall, 552 U.S., at 59, 128 S. Ct. 586, 169 L. Ed. 2d 445 (“Gall’s self-motivated rehabilitation . . . lends strong support to the conclusion that imprisonment was not necessary to deter Gall from engaging in future criminal conduct or to protect the public from his future criminal acts” (citing §§ 3553(a)(2)(B)-(C))). As recognized by Pepper’s probation officer, Pepper’s steady employment, as well as his successful completion of a 500-hour drug treatment program and his drug-free condition, also suggest a diminished need for “educational or vocational training ... or other correctional treatment.” § 3553(a)(2)(D). Finally, Pepper’s exemplary post-sentencing conduct may be taken as the most accurate indicator of “his present purposes and tendencies and significantly to suggest the period of restraint and the kind of
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discipline that ought to be imposed upon him.” Ashe, 302 U.S., at 55, 58 S. Ct. 59, 82 L. Ed. 43. Accordingly, evidence of Pepper’s postsentencing rehabilitation bears directly on the District Court’s overarching duty to “impose a sentence sufficient, but not greater than necessary,” to serve the purposes of sentencing. § 3553(a).
In sum, the Court of Appeals’ ruling prohibiting the District Court from considering any evidence of Pepper’s postsentencing rehabilitation at re-sentencing conflicts with longstanding principles of federal sentencing law and contravenes Congress’ directives in §§ 3661 and 3553(a).
C
Amicus nevertheless advances two principal arguments in defense of the Court of Appeals’ ruling: (1) 18 U.S.C. § 3742(g)(2), which restricts the discretion of a resentencing court on remand to impose a non-Guidelines sentence, effectively forecloses consideration of a defendant’s post-sentencing rehabilitation; and (2) permitting district courts to consider postsentencing rehabilitation would defeat Congress’ objectives under § 3553(a). We are not persuaded.
1
Amicus'' main argument relies on 18 U.S.C. § 3742(g)(2), a provision that the Court of Appeals did not cite below. That provision states that when a sentence is set aside on appeal, the district court to which the case is remanded:
*216“shall not impose a sentence outside the applicable guidelines range except upon a ground that—
“(A) was specifically and affirmatively included in the written statement of reasons required by section 3553(c) in connection with the previous sentencing of the defendant prior to the appeal; and
“(B) was held by the court of appeals, in remanding the case, to be a permissible ground of departure.”
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In operation, § 3742(g)(2) restricts the discretion of a district court on remand by precluding the court from imposing a sentence outside the Guidelines range except upon a “ground of departure” that was expressly relied upon in the prior sentencing and upheld on appeal. Amicus thus correctly contends that, on its face, § 3742(g)(2) effectively forecloses a resentencing court from considering evidence of a defendant’s postsentenc-ing rehabilitation for purposes of imposing a non-Guidelines sentence because, as a practical matter, such evidence did not exist at the time of the prior sentencing. As the Government concedes, however, § 3742(g)(2) is invalid after Booker.
As we have explained, Booker held that where judicial factfinding increases a defendant’s applicable Sentencing Guidelines range, treating the Guidelines as mandatory in those circumstances would violate the defendant’s Sixth Amendment right to be tried by a jury and to have every element of an offense proved by the Government beyond a reasonable doubt. See supra, at 489-490, 179 L. Ed6. 2d, at 213-214. We recognized in Booker that, although the SRA permitted departures from the applicable Guidelines range in limited circumstances,9 “departures are not available in every case, and in fact are unavailable in most.” 543 U.S., at 234, 125 S. Ct. 738, 160 L. Ed. 2d 621. Because in those instances, “the judge is bound to impose a sentence within the Guidelines range,” we concluded that the availability of departures in certain circumstances “does not avoid the constitutional issue.” Ibid.
To remedy the constitutional problem, we rendered the Guidelines effectively advisory by invalidating two provisions of the SRA: 18 U.S.C. § 3553(b)(1) (2000 ed., Supp. IV), which generally required sentencing courts to impose a sentence within the applicable Guidelines range, and § 3742(e)
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(2000 ed. and Supp. IV), which prescribed the standard of appellate review, including de novo review of Guidelines departures. 543 U.S., at 259, 125 S. Ct. 738, 160 L. Ed. 2d 621. We invalidated these provisions even though we recognized that mandatory application of the Guidelines would not always result in a Sixth Amendment violation.10 Indeed, although the Government suggested in Booker that we render the Guidelines advisory only in cases in which the Constitution prohibits judicial factfinding, we rejected that two-track proposal, reasoning that “Congress would not have authorized a mandatory system in some cases and *217a nonmandatory system in others, given the administrative complexities that such a system would create.” Id., at 266, 125 S. Ct. 738, 160 L. Ed. 2d 621; see Dillon, 560 U.S., at 829-830, 130 S. Ct. 2683, 177 L. Ed. 2d 271 (“The incomplete remedy we rejected in Booker would have required courts to treat the Guidelines differently in similar proceedings, leading potentially to unfair results and considerable administrative challenges”).
We did not expressly mention § 3742(g)(2) in Booker,11 but the rationale we set forth in that opinion for invalidating §§ 3553(b)(1) and 3742(e) applies equally to § 3742(g)(2). As with those provisions, § 3742(g)(2) requires district courts effectively to treat the Guidelines as mandatory in an entire set of cases. Specifically, § 3742(g)(2) precludes a district court on remand from imposing a sentence “outside the applicable guidelines range” except upon a “ground of departure” that was expressly relied upon by the court at the prior sentencing and upheld by the court of appeals. In circumstances in which the district court did not rely upon such a departure ground at the prior sentencing, § 3742(g)(2) would
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require the court on remand to impose a sentence within the applicable Guidelines range, thus rendering the Guidelines effectively mandatory. Because in a large set of cases, judicial factfinding will increase the applicable Guidelines range beyond that supported solely by the facts established by the jury verdict (or guilty plea), requiring a sentencing judge on remand to apply the Guidelines range, as § 3742(g)(2) does, will often result in a Sixth Amendment violation for the reasons we explained in Booker. Accordingly, as with the provisions in Booker, the proper remedy here is to invalidate § 3742(g)(2).
The sentencing proceeding at issue in Booker itself illustrates why § 3742(g)(2) cannot withstand Sixth Amendment scrutiny. The District Court in Booker increased the defendant’s then-mandatory Guidelines range based on a drug-quantity finding that it, rather than the jury, made. 543 U.S., at 227, 125 S. Ct. 738, 160 L. Ed. 2d 621. After we held that the Guidelines must be treated as advisory, we remanded the case for resen-tencing. Id., at 267, 125 S. Ct. 738, 160 L. Ed. 2d 621. Had § 3742(g)(2) remained valid after Booker, the District Court on remand would have been required to sentence within the Guidelines range because it did not depart from the Guidelines at the original sentencing. Accordingly, the resentencing judge in Booker would have been required under § 3742(g)(2) to impose a Guidelines sentence based on judge-found facts concerning drug quantity, the precise result that Booker forbids.
The same result would occur in any sentencing in which a district court erroneously refuses to impose a sentence outside the Guidelines range “based on a misunderstanding of its authority to depart under or vary from the Guidelines.” Reply Brief for United States 16. For example, if § 3742(g)(2) remained valid, there would be no remedy at resentencing if a district court erroneously believed the Guidelines were presumptively reasonable, see Nelson v. United States, 555 U.S. 350, 352, 129 S. Ct. *218890, 172 L. Ed. 2d 719 (2009) (per curiam), or if it mistakenly
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thought that a non-Guidelines sentence required extraordinary circumstances, see Gall, 552 U.S., at 47, 128 S. Ct. 586, 169 L. Ed. 2d 445, or if it incorrectly concluded that it could not vary from the Guidelines based on a policy disagreement with their disparate treatment of crack and powder cocaine, see Kimbrough, 552 U.S., at 101, 128 S. Ct. 558, 169 L. Ed. 2d 481. In such cases, the district court at the initial sentencing proceeding will necessarily have imposed a sentence within the Guidelines range, and thus § 3742(g)(2) would require the imposition of a Guidelines sentence on remand. See Reply Brief for Petitioner 3-5 (describing further categories of cases where “the Booker remedy would be entirely unavailable if § 3742(g)(2) were valid”).
To be sure, applying § 3742(g)(2) at resentencing would not always result in a Sixth Amendment violation. For example, where the applicable Guidelines range rests solely on facts found by a jury beyond a reasonable doubt, application of § 3742(g)(2) at resen-tencing would not render the sentence constitutionally infirm. But, as explained above, that possibility was equally true with respect to the sentencing provisions we invalidated in Booker. See supra, at 495, 179 L. Ed. 2d, at 216-217. As with those provisions, “we cannot assume that Congress, if faced with the statute’s invalidity in key applications, would have preferred to apply the statute in as many other instances as possible.” 543 U.S., at 248, 125 S. Ct. 738, 160 L. Ed. 2d 621. Just as we rejected a two-track system in Booker that would have made the Guidelines mandatory in some cases and advisory in others, we reject a partial invalidation of § 3742(g)(2) that would leave us with the same result.
The fact that § 3742(g)(2) permits a resentencing court on remand to impose a non-Guidelines sentence in cases where the prior sentence expressly relied upon a departure upheld by the court of appeals also does not cure the constitutional infirmity. As explained above, we observed in Booker that the availability of departures from the applicable Guidelines ranges in specified circumstances “does not avoid the constitutional
[562 U.S. 498]
issue.” Id.., at 234, 125 S. Ct. 738, 160 L. Ed. 2d 621. Because “departures are not available in every case, and in fact are unavailable in most,” ibid., we held that remedying the Sixth Amendment problem required invalidation of § 3553(b)(1). That same remedial approach requires us to invalidate § 3742(g)(2).12
Amicus contends that any constitutional infirmity in § 3742(g)(2) can be remedied by invalidating § 3742(j)(l)(B) rather than § 3742(g)(2). Brief for Amicus Curiae *219in Support of Judgment Below 21-22. Section 3742(j)(l)(B) provides that a “ground of departure” is “permissible” for purposes of § 3742(g)(2)(B) only if it is, inter alia, “authorized under section 3553(b).” In Booker, we noted that “statutory cross-references” to the SRA provisions we invalidated were also constitutionally infirm. 543 U.S., at 259, 125 S. Ct. 738, 160 L. Ed. 2d 621. Because § 3742(j)(l)(B) incorporates a cross-reference to § 3553(b)(1), one of the provisions we invalidated in Booker, amicus suggests that invalidating § 3742(j)(l)(B) would cure any constitutional defect in § 3742(g)(2)(B). As the Government explains, however, even if § 3742(j)(l)(B) were invalidated and a district court could depart on any ground at an initial sentencing, the district court would not be able to depart on any new ground at resen-tencing so long as § 3742(g)(2) remains
[562 U.S. 499]
in force. Because amicus’ proposed solution would still result in the Guidelines being effectively mandatory at resentencing in an entire set of cases, it fails to remedy the fundamental constitutional defect of § 3742(g)(2).
2
Amicus’ next cluster of arguments focuses on Congress’ sentencing objectives under § 3553(a). Preliminarily, amicus contends that even if § 3742(g)(2) is constitutionally invalid, that provision reflects a congressional policy determination that only information available at the time of original sentencing should be considered, and that this policy determination should inform our analysis of whether § 3553(a) permits consideration of postsentencing rehabilitation evidence. This argument, however, is based on a faulty premise.
Contrary to amicus’ contention, § 3742(g)(2) does not reflect a congressional purpose to preclude consideration of evidence of postsentencing rehabilitation at resentencing. To be sure, § 3742(g)(2) has the incidental effect of limiting the weight a sentencing court may place on postsentencing rehabilitation by precluding the court from resentencing outside the Guidelines range on a “ground of departure” on which it did not previously rely. But on its face, nothing in § 3742(g)(2) prohibits a district court from considering postsentencing developments— including postsentencing rehabilitation—in selecting a sentence within the applicable Guidelines range. Section 3742(g)(2) also does not apply to resentencings that occur for reasons other than when a sentence is overturned on appeal and the case is remanded (e.g., when a sentence is set aside on collateral review under 28 U.S.C. § 2255). In such circumstances, § 3742(g)(2) does not restrict a district court at all, much less with respect to consideration of postsen-tencing developments. Accordingly, because we see no general congressional policy reflected in § 3742(g)(2) to preclude resentencing courts from considering
[562 U.S. 500]
postsentencing information,13 that provision has no bearing on our analysis of whether § 3553(a) *220permits consideration of evidence of postsentencing rehabilitation.
As we explained above, evidence of postsentencing rehabilitation may be highly relevant to several of the sentencing factors that Congress has specifically instructed district courts to consider. See supra, at 491-493, 179 L. Ed. 2d, at 214-215 (discussing §§ 3553(a), (a)(1), (a)(2)(B)-(D)). Am-icus, however, argues that consideration of postsentencing rehabilitation is inconsistent with two sentencing factors: § 3553(a)(5), which directs sentencing courts to consider “any pertinent policy statement” of the Sentencing Commission, and § 3553(a)(6), which requires courts to consider “the need to avoid unwarranted sentenc[ing] disparities among defendants with similar records who have been found guilty of similar conduct.”
With regard to § 3553(a)(5), amicus points to the Sentencing Commission’s policy statement in USSG § 5K2.19, which provides that “[p]ost-sentencing rehabilitative efforts, even if exceptional, undertaken by a defendant after imposition of a term of imprisonment for the instant offense [,] are not an appropriate basis for a downward departure when re-sentencing the defendant for that offense.” According to amicus, that policy statement is “clear and unequivocal,” and as an
[562 U.S. 501]
exercise of the Sentencing Commission’s “core function,” should be given effect. Brief for Amicus Curiae in Support of Judgment Below 31-32.
To be sure, we have recognized that the Commission post-Booker continues to “fil[l] an important institutional role” because “ [i]t has the capacity courts lack to base its determinations on empirical data and national experience, guided by a professional staff with appropriate expertise.” Kimbrough, 552 U.S., at 109, 128 S. Ct. 558, 169 L. Ed. 2d 481 (internal quotation marks omitted). Accordingly, we have instructed that district courts must still give “respectful consideration” to the now-advisory Guidelines (and their accompanying policy statements). Id., at 101, 128 S. Ct. 558, 169 L. Ed. 2d 481. As amicus acknowledges, however, our post-Booker decisions make clear that a district court may in appropriate cases impose a non-Guidelines sentence based on a disagreement with the Commission’s views. See id., at 109-110, 128 S. Ct. 558, 169 L. Ed. 2d 481. That is particularly true where, as here, the Commission’s views rest on wholly unconvincing policy rationales not reflected in the sentencing statutes Congress enacted.
The commentary to USSG § 5K2.19 expresses the Commission’s view that departures based on postsentencing rehabilitation would “(1) be inconsistent with the policies established by Congress under 18 U.S.C. § 3624(b) [governing good time credit] and other statutory provisions for reducing the time to be served by an imprisoned person; and (2) inequitably benefit only those who gain the opportunity to be resentenced de novo.” With regard to the first proffered rationale, a sentencing reduction based on postsentencing rehabilitation can hardly be said to be “inconsistent with the policies” under*221lying an award of good time credit under § 3624(b) because the two serve distinctly different penological interests.14 Indeed, the difference between the two is
[562 U.S. 502]
reflected most obviously in the fact that the BOP has no authority to award good time credit where, as in this case, the defendant’s good behavior occurs after a sentence has already been served.15 The Commission’s second proffered rationale fares no better. To be sure, allowing district courts to consider evidence of postsen-tencing rehabilitation may result in disparate treatment between those defendants who are sentenced properly and those who must be resen-tenced. But that disparity arises not because of arbitrary or random sentencing practices, but because of the ordinary operation of appellate sentencing review.
In a closely related vein, amicus argues that consideration of postsen-tencing rehabilitation is inconsistent with § 3553(a)(6), which requires sentencing courts to consider the need to avoid unwarranted sentencing disparities. The Court of Appeals also rested its holding on this ground, reasoning
[562 U.S. 503]
that “ ‘allowing [postsen-tencing rehabilitation] evidence to influence [defendant’s] sentence would be grossly unfair to the vast majority of defendants who receive no sentencing-court review of any positive post-sentencing rehabilitative efforts.’ ” 570 F.3d, at 965 (quoting McMannus, 496 F.3d, at 852, n. 4). But [25] amicus points to no evidence, nor are we aware of any, suggesting that Congress enacted § 3553(a)(6) out of a concern with disparities resulting from the normal trial and sentencing process.16 The differences in procedural opportunity that may result because some defendants are inevitably sentenced in error and must be resen-tenced are not the kinds of “unwar*222ranted” sentencing disparities that Congress sought to eliminate under § 3553(a)(6). Cf. United States v. LaBonte, 520 U.S. 751, 761-762, 117 S. Ct. 1673, 137 L. Ed. 2d 1001 (1997) (disparity arising from exercise of prosecutorial discretion not unwarranted); United States v. Rhodes, 145 F.3d 1375, 1381 (CADC 1998) (“Distinguishing between prisoners whose convictions are reversed on appeal and all other prisoners hardly seems ‘unwarranted’ ”).
As the Government explains, moreover, the logic of the Court of Appeals’ approach below—i.e., that “post-sentence rehabilitation is not relevant ... because the district court could not have considered that evidence at the time of the original sentencing,” 570 F.3d, at 965 (internal quotation marks omitted)—would require sentencing courts categorically to ignore not only postsentencing rehabilitation, but
[562 U.S. 504]
any postsentencing information, including, for example, evidence that a defendant had committed postsen-tencing offenses. Our precedents, however, provide no basis to support such a categorical bar. See, e.g., Wasman, 468 U.S., at 572, 104 S. Ct. 3217, 82 L. Ed. 2d 424 (“[A] sentencing authority may justify an increased sentence by affirmatively identifying relevant conduct or events that occurred subsequent to the original sentencing proceedings”); cf. North Carolina v. Pearce, 395 U.S. 711, 723, 89 S. Ct. 2072, 23 L. Ed. 2d 656 (1969). Indeed, even the Court of Appeals below does not accept the logical consequence of its approach as it permits district courts to consider postsentencing conduct that would support a higher sentence. See United States v. Stapleton, 316 F.3d 754, 757 (CA8 2003). Nothing in §§ 3553(a) and 3661, however, remotely suggests that Congress intended district courts to consider only postsentencing evidence detrimental to a defendant while turning a blind eye to favorable evidence of a defendant’s postsentenc-ing rehabilitation. Cf. United States v. Jones, 460 F.3d 191, 196 (CA2 2006) (“Obviously, the discretion that Booker accords sentencing judges to impose non-Guidelines sentences cannot be an escalator that only goes up”).
Finally, we note that §§ 3553(a)(5) and (a)(6) describe only two of the seven sentencing factors that courts must consider in imposing sentence. At root, amicus effectively invites us to elevate two § 3553(a) factors above all others. We reject that invitation. See Gall, 552 U.S., at 49-50, 128 S. Ct. 586, 169 L. Ed. 2d 445 ( instructing sentencing courts to “consider all of the § 3553(a) factors” (emphasis added)).
D
For the reasons stated above, we hold that the Court of Appeals erred in categorically precluding the District Court from considering evidence of Pepper’s postsentencing rehabilitation after his initial sentence was set aside on appeal. District courts post -Booker may consider evidence of a defendant’s postsentencing rehabilitation at resentencing and
[562 U.S. 505]
such evidence may, in appropriate cases, support a downward variance from the advisory Guidelines range.17
The Government informs us that, in granting Pepper’s motion for re*223lease pending disposition of this appeal, see n. 5, supra, the District Court stated that it would not have exercised its discretion to grant Pepper a downward variance based on postsentencing rehabilitation. That statement, however, was made in light of the Court of Appeals’ erroneous views regarding postsentencing rehabilitation evidence. Because we expressly reject those views today, it is unclear from the record whether the District Court would have imposed the same sentence had it properly considered the extensive evidence of Pepper’s postsentencing rehabilitation. On remand, the District Court should consider and give appropriate weight to that evidence, as well as any additional evidence concerning Pepper’s conduct since his last sentencing in January 2009. Accordingly, we vacate the Eighth Circuit’s judgment in respect to Pepper’s sentence and remand the case for resentencing consistent with this opinion.
Ill
The second question presented in this case merits only a brief discussion. As noted above, the original sentencing judge in this case granted Pepper a 40-percent downward departure pursuant to USSG § 5K1.1 based on Pepper’s substantial assistance and sentenced him to 24 months’ imprisonment. When the Court of Appeals vacated that sentence in Pepper II, and again in Pepper III, the case was reassigned on remand to Chief Judge Reade. In resentencing
[562 U.S. 506]
Pepper, Chief Judge Reade ruled that she was not bound by the prior sentencing judge’s decision to grant a 40-percent downward departure and instead granted only a 20-percent downward departure, which the Court of Appeals upheld in Pepper IV. Pepper argues that the law of the case doctrine required Chief Judge Reade to apply the same 40-percent departure granted by the original sentencing judge. We disagree.
Preliminarily, we note that the mandates in Pepper II and Pepper III were “general remand [s] for resen-tencing,” which “did not place any limitations on the discretion of the newly assigned district court judge in resentencing Pepper.” 570 F.3d, at 963. In his merits briefs to this Court, Pepper does not challenge the scope or validity of the Court of Appeals’ mandate ordering de novo resentenc-ing, and thus has abandoned any argument that the mandate itself restricted the District Court from imposing a different substantial assistance departure.18 The only question before us is whether the law of the case doctrine required Chief Judge Reade to adhere to the original sentencing judge’s decision granting a 40-percent downward departure.
Although we have described the “law of the case [a]s an amorphous concept,” “[a]s most commonly defined, the doctrine posits that when a court decides upon a rule of law, that decision should continue to govern the same issues in subsequent stages in the same case.” Arizona v. California, 460 U.S. 605, 618, 103 S. Ct. 1382, 75 L. Ed. 2d 318 (1983). This doctrine *224“directs a court’s discretion, it does not limit the tribunal’s power.” Ibid. Accordingly, the doctrine “does not apply if the court is ‘convinced that [its prior decision] is clearly erroneous and
[562 U.S. 507]
would work a manifest injustice.’” Agostini v. Felton, 521 U.S. 203, 236, 117 S. Ct. 1997, 138 L. Ed. 2d 391 (1997) (quoting Arizona, 460 U.S., at 618, n. 8, 103 S. Ct. 1382, 75 L. Ed. 2d 318; alteration in original).
Pepper argues that, because the original sentencing judge’s decision to grant the 40-percent departure was never set aside by the Court of Appeals or this Court, it constituted the law of the case. As such, Pepper contends that Chief Judge Reade should not have disturbed that ruling absent “compelling justification” for overturning it. Brief for Petitioner 56. According to Pepper, because Chief Judge Reade identified no such justification, the law of the case doctrine required her to adhere to the 40-percent departure granted by the original sentencing judge.
As the Government explains, however, the Court of Appeals in Pepper III set aside Pepper’s entire sentence and remanded for a de novo resen-tencing. See 518 F.3d, at 949, 953. Thus, even assuming, arguendo, that the original sentencing court’s decision to impose a 40-percent departure was at one point law of the case, Pepper III effectively wiped the slate clean. To be sure, Pepper III vacated Pepper’s 24-month sentence on grounds unrelated to the substantial assistance departure, but that fact does not affect our conclusion. “A criminal sentence is a package of sanctions that the district court utilizes to effectuate its sentencing intent.” United States v. Stinson, 97 F.3d 466, 469 (CA11 1996) (per curiam). Because a district court’s “original sentencing intent may be undermined by altering one portion of the calculus,” United States v. White, 406 F.3d 827, 832 (CA7 2005), an appellate court when reversing one part of a defendant’s sentence “may vacate the entire sentence ... so that, on remand, the trial court can reconfigure the sentencing plan ... to satisfy the sentencing factors in 18 U.S.C. § 3553(a),” Greenlaw v. United States, 554 U.S. 237, 253, 128 S. Ct. 2559, 171 L. Ed. 2d 399 (2008). That is precisely what the Eighth Circuit did here.
Accordingly, because the Court of Appeals in Pepper III remanded for de novo resentencing, we conclude that Chief
[562 U.S. 508]
Judge Reade was not bound by the law of the case doctrine to apply the same 40-percent departure that had been applied at Pepper’s prior sentencing.
For the reasons stated above, the judgment of the United States Court of Appeals for the Eighth Circuit is vacated in part and affirmed in part, and the case is remanded for resen-tencing consistent with this opinion.
It is so ordered.
Justice Kagan took no part in the consideration or decision of this case.
. Although the charge to which Pepper pleaded guilty carried a mandatory minimum of 120 months’ imprisonment, the mandatory minimum did not apply because he was eligible for safety-valve relief pursuant to 18 U.S.C. § 3553(f) (2000 ed.) and § 5C1.2 of the United States Sentencing Commission, Guidelines Manual (Nov. 2003) (USSG).
. USSG § 5K1.1 provides that a court may depart from the Guidelines “[u]pon motion of the government stating that the defendant has provided substantial assistance in the investigation or prosecution of another person who has committed an offense.” Pepper provided information to Government investigators and a grand jury concerning two other individuals involved with illegal drugs and guns.
. The court also cited Pepper’s lack of a violent history and, to a lesser extent, the need to avoid unwarranted sentencing disparity with Pepper’s co-conspirators. App. 144-145.
. The Court of Appeals also held that the District Court “further erred by considering Pepper’s lack of violent history, which history had already been accounted for in the sentencing Guidelines calculation, and by considering sentencing disparity among Pepper’s co-defendants without adequate foundation and explanation.’’ Pepper II, 486 F.3d, at 413.
. After the District Court resentenced Pepper to 65 months’ imprisonment, Pepper was returned to federal custody. On July 22, 2010, after we granted Pepper’s petition for a writ of certiorari, the District Court granted his motion for release pending disposition of the case here.
. Compare, e.g., United States v. Lorenzo, 471 F.3d 1219, 1221 (CA11 2006) (per curiam) (precluding consideration of postsentencing rehabilitative conduct); United States v. Sims, 174 F.3d 911, 913 (CA8 1999) (same), with United States v. Lloyd, 469 F.3d 319, 325 (CA3 2006) *212(permitting consideration of postsentencing rehabilitation in exceptional cases); United States v. Hughes, 401 F.3d 540, 560, n. 19 (CA4 2005) (instructing District Court to adjust Guidelines calculation on remand “if new circumstances have arisen or events occurred since [defendant] was sentenced that impact the range prescribed by the guidelines’’).
. We appointed Adam G. Ciongoli to brief and argue the case, as amicus curiae, in support of the Court of Appeals’judgment. 561 U.S. 1042, 131 S. Ct. 32, 177 L. Ed. 2d 1122 (2010). Mr. Ciongoli has ably discharged his assigned responsibilities.
. Of course, sentencing courts’ discretion under § 3661 is subject to constitutional constraints. See, e.g., United States v. Leung, 40 F.3d 577, 586 (CA2 1994) (“A defendant’s race or nationality may play no adverse role in the administration of justice, including at sentencing”).
. See 18 U.S.C. § 3553(b)(1) (2000 ed., Supp. IV) (permitting departures where the judge “finds that there exists an aggravating or mitigating circumstance of a kind, or to a degree, not adequately taken into consideration by the Sentencing Commission’’).
. For example, in the pre-Booker regime, if the applicable Guidelines range depended solely on facts found by a jury beyond a reasonable doubt, requiring a judge to sentence within that range would not run afoul of the Sixth Amendment.
. See Dillon, 560 U.S., at 839, n. 5, 130 S. Ct. 2683, 177 L. Ed. 2d 271 (Stevens, J., dissenting) (citing § 3742(g)(2) as “one additional provision of the [SRA that] should have been excised, but was not, in order to accomplish the Court’s remedy’’).
. Amicus National Association of Criminal Defense Lawyers (NACDL) argues that, because § 3742(g)(2)(B) permits a non-Guidelines sentence only with respect to certain “departures,” that provision “appears to preclude sentencing courts on remand from granting any and all variances under Section 3553(a).” Brief for NACDL 11 (emphasis added). In Irizarry v. United States, 553 U.S. 708, 128 S. Ct. 2198, 171 L. Ed. 2d 28 (2008), we held that a “ ‘[departure’ is a term of art under the Guidelines and refers only to non-Guidelines sentences imposed under the framework set out in the Guidelines”; in contrast, a “variance” refers to a non-Guidelines sentence outside the Guidelines framework. Id., at 714, 128 S. Ct. 2198, 171 L. Ed. 2d 28. Irizany's holding construed the term “departure” in Rule 32(h) of the Federal Rules of Criminal Procedure. Because we conclude that § 3742(g)(2) is constitutionally infirm and must be invalidated, we need not decide whether its reference to “departure[s]” includes variances.
. For those of us for whom it is relevant, the legislative history of § 3742(g)(2) confirms that the provision, enacted as part of the PROTECT Act of 2003, § 401(e), 117 Stat. 671, was not aimed at prohibiting district courts from considering postsentencing developments. Rather, it was meant to ensure that under the then-mandatory Guidelines system, when a particular departure was reversed on appeal, the district court could not impose the same sentence on remand on the basis of a different departure. See H. R. Conf. Rep. No. 108-66, pp. 58-59 (2003) (noting that § 401 of the PROTECT Act, inter alia, “prevent[s] sentencing courts, upon remand, from imposing the same *220illegal departure on a different theory”). Like the provisions invalidated in Booker, then, the purpose of § 3742(g)(2) was “to make Guidelines sentencing even more mandatory than it had been.” United States v. Booker, 543 U.S. 220, 261, 125 S. Ct. 738, 160 L. Ed. 2d 621 (2005). As we recognized in Booker, that purpose has “ceased to be relevant.” Ibid.
. An award of good time credit by the Bureau of Prisons (BOP) does not affect the length of a court-imposed sentence; rather, it is an administrative reward ‘to provide an incentive for prisoners to ‘complly] with institutional disciplinary regulations.’ ” Barber v. Thomas, 560 U.S. 474, 482, 130 S. Ct. 2499, 177 L. Ed. 2d 1 (2010) (quoting 18 U.S.C. § 3624(b); alteration in original). Such credits may be revoked at any time before the date of a prisoner’s release. See § 3624(b)(2). In contrast, a court’s imposition of a reduced sentence based on postsentencing rehabilitation changes the very terms of imprisonment and “recognizes that the [defendant’s] conduct since his initial sentencing warrants a less severe criminal punishment.’’ Brief for United States 50. Once imposed, a sentence may be modified only in very limited circumstances. See § 3582(c).
. Amicus points to two other procedural mechanisms that may shorten a defendant’s sentence—early termination of a term of supervised release, see § 3583(e)(1), and the potential for sentencing reductions based on postsentencing substantial assistance, see Fed. Rule Crim. Proc. 35(b)—but neither presents an adequate substitute for a district court’s consideration of postsen-tencing rehabilitation. Supervised release follows a term of imprisonment and serves an entirely different purpose than the sentence imposed under § 3553(a). See United States v. Johnson, 529 U.S. 53, 59, 120 S. Ct. 1114, 146 L. Ed. 2d 39 (2000) (“Supervised release fulfills rehabilitative ends, distinct from those served by incarceration’’). Rule 35(b) departures address only postsen-tencing cooperation with the Government, not postsentencing rehabilitation generally, and thus a defendant with nothing to offer the Government can gain no benefit from Rule 35(b).
. Indeed, some defendants will have a longer period of time between initial custody and trial, or between trial and sentencing, and those defendants—particularly if they are released on bail—will have a greater opportunity to demonstrate postoffense, presentencing rehabilitation. Even before Booker, the lower courts uniformly held that evidence of such rehabilitation could provide a basis for departing from the applicable Guidelines. See USSG App. C, Arndt. 602, comment., p. 74 (Nov. 2003) (“[Departures based on extraordinary post-offense rehabilitative efforts prior to sentencing . . . have been allowed by every circuit that has ruled on the matter’’).
. Of course, we do not mean to imply that a district court must reduce a defendant’s sentence upon any showing of postsentencing rehabilitation. Nor do we mean to preclude courts of appeals from issuing limited remand orders, in appropriate cases, that may render evidence of postsen-*223tencing rehabilitation irrelevant in light of the narrow purposes of the remand proceeding. See, e.g., United States v. Bernardo Sanchez, 569 F.3d 995, 1000 (CA9 2009).
. In any event, as the Court of Appeals recognized, neither Pepper II nor Pepper III held that a 40-percent downward departure was the only reasonable departure that a sentencing court could grant for Pepper’s substantial assistance; rather, the only issue those opinions actually decided was that a “40% downward departure was not an abuse of discretion.’’ 570 F.3d, at 963-964.