On Appeal from the United States District Court for the District of New Jersey (D.C. No. 1:20-cv-14835) District Judge: Honorable Christine P. O’Hearn

Argued on July 9, 2025 Before: KRAUSE, MATEY, and PHIPPS, Circuit Judges (Filed: October 8, 2025)Page 2 Tadhg Dooley David R. Roth WIGGIN & DANA One Century Tower 265 Church Street New Haven, CT 06510

Riley Gordon Sharon Nunn Kevin Yang [ARGUED] YALE LAW SCHOOL 127 Wall Street New Haven, CT 06511

Court Appointed Amicus Curiae Counsel

Paul T. Crane [ARGUED] UNITED STATES DEPARTMENT OF JUSTICE APPELLATE SECTION Room 7323 950 Pennsylvania Avenue NW Washington, DC 20530

John T. Stinson, Jr. OFFICE OF UNITED STATES ATTORNEY Camden Federal Building & Courthouse 401 Market Street Camden, NJ 08101

Page 3OPINION OF THE COURT

PHIPPS, Circuit Judge .

A federal statute allows good conduct time credit of up to 54 days each year for persons serving federal sentences. In this case, a federal inmate with a seventeen-and-a-half-year sentence asserts that after the First Step Act of 2018 amended the statute, he became eligible for 54 days of good conduct time credit not only for each full year of his sentence but also for the last six months of his sentence. See First Step Act of 2018, Pub. L. No. 115-391, tit. I, § 102(b)(1), 132 Stat. 5194, 5210 (codified at 18 U.S.C. § 3624(b)(1)). Instead of allowing the possibility of a full 54 days of good conduct time credit for the last six months, the Federal Bureau of Prisons, commonly referred to as the ‘BOP,’ has interpreted the statute as amended by the First Step Act to require prorating the good conduct time credit on a daily basis for that time period. Using that method, the BOP calculated that the prisoner would be eligible for 26, not 54, days of credit for the last six months of his sentence. To obtain the additional 28-day credit, the inmate petitioned for a writ of habeas corpus, and the District Court denied that petition. On de novo review of that pure question of law, we will affirm the order of the District Court.

Since 1867, federal prisoners have been statutorily eligible for reduced sentences based on their good conduct while incarcerated.¹ The modern system for granting prisoners such Page 4good conduct time credit began with the enactment of the Sentencing Reform Act of 1984.² Under that legislation, federal prisoners were eligible for a good conduct time credit “of fifty-four days at the end of each year of [their] term of imprisonment.' Pub. L. No. 98-473, tit. II, ch. II, 98 Stat. 1987, 2008–09 (codified as amended at 18 U.S.C. § 3624(b)(1)). That credit was withheld if 'the Bureau of Prisons determine[d] that, during that year, [a prisoner] ha[d] not satisfactorily complied with . . . institutional disciplinary regulations,” and any such credit would be “prorated” for the “last year or portion of a year of the term of imprisonment.” Id. at 2009. The legislation further provided that any proration had to be credited “within the last six weeks of the sentence.” Id. An amendment by the Violent Crime Control and Law Enforcement Act of 1994 made good conduct time credit “subject to determination by the Bureau of Prisons that, during that year, the prisoner has displayed exemplary compliance with such institutional disciplinary regulations.' Pub. L. No. 103-322, tit. II, subtitle D, § 20405, 108 Stat. 1796, 1825–Page 5 26 (codified as amended at 18 U.S.C. § 3624(b)(1)). It also added the phrase ‘up to’ before ‘54 days’ but retained the root term 'prisoner's term of imprisonment,' as well as the proration provision. Id. at 1826. But even with that amendment and another in 1996, 3 the statute had a critical ambiguity: it was unclear if the root term, ‘prisoner’s term of imprisonment,’ referred to the initially imposed prison term or to the actual prison term served, which may be less than the initial term based on earned good conduct time credit.

The Supreme Court resolved that ambiguity in Barber v. Thomas , 560 U.S. 474 (2010). It did so by evaluating “[t]he statute's language and its purpose, taken together[.]' Id. at 480. As far as the statutory text, the Supreme Court focused on the provisions stating that good conduct time credit would be awarded “at the end of each year” and that any such award would be subject to the BOP’s determination that “during that year' the inmate behaved in an exemplary fashion. Id. (emphasis removed) (quoting 18 U.S.C. § 3624(b)(1) (2006)). From there, the Supreme Court reasoned that the statute's purpose was to implement “a system of retrospective award,” not 'prospective entitlement.' Id. at 481 (citation omitted). Based on that analysis, the Supreme Court held that good conduct time credit was available only for the term of imprisonment actually served by the prisoner – not for the term of imprisonment imposed by the sentencing judge. Id. at 48083. Thus, 54 days of good conduct time credit could be awarded “for each full year of imprisonment that [a prisoner]Page 6 serves and a proportionally adjusted amount of credit for any additional time served that is less than a full year.” Id. at 480.

The First Step Act of 2018 amended the statutory provisions regarding good conduct time credit in several respects. That legislation removed text to transform the root term ‘prisoner’s term of imprisonment’ into ‘prisoner’s sentence.’ First Step Act of 2018, Pub. L. No. 115-391, tit. I, § 102(b)(1)(A)(i), 132 Stat. 5194, 5210 (codified at 18 U.S.C. § 3624(b)(1)). And the phrase ‘at the end of each year’ was revised to read ‘for each year.’ Id. With that change to 'for each year,’ the First Step Act deleted the term ‘prorated’ and other language regarding the proration process, such as the phrase ‘portion of a year’ and the specification that the credit be awarded 'within the last six weeks of the sentence.' Id. Altogether, after the First Step Act amendments, which are visualized below, good conduct time credits were not purely a retrospective reward but rather took on some attributes of a prospective entitlement, albeit one subject to BOP review:

Subject to paragraph (2), a prisoner who is serving a term of imprisonment of more than 1 year other than a term of imprisonment for the duration of the prisoner’s life, may receive credit toward the service of the prisoner's sentence, beyond the time served, of up to 54 days at the end of for each year of the prisoner's term of imprisonment, beginning at the end of the first year of the term sentence imposed by the court , subject to determination by the Bureau of Prisons that, during that year, the prisoner has displayed exemplary compliance with institutional disciplinary regulations . . . . Subject to paragraph (2), credit for the last year or portion of a year of the a term of imprisonment shall be prorated and credited within the last six weeks of

18 U.S.C. § 3624(b)(1) (strikethroughs representing deletions and emphases representing additions made by the First Step Act, tit. I, § 102(b)(1)(A)(i), 132 Stat. at 5210).

In response to those amendments, the BOP published a notice of proposed rulemaking on December 31, 2019, with a revised method for calculating good conduct time credit. Good Conduct Time Credit Under the First Step Act , 84 Fed. Reg. 72,274, 72,274 (Dec. 31, 2019). See generally 5 U.S.C. § 553(b) (setting forth the process for proposing agency rules). Under that new approach, the BOP would calculate credit “for each year of the sentence imposed by the court , instead of for each year of actual time served .” Good Conduct Time Credit Under the First Step Act , 84 Fed. Reg. at 72,274. And when the last increment of the sentence is for a portion of a year, the BOP would prorate good conduct time credit at the rate of 0.148 credits per day (0.148 is the maximum 54 days of credit divided by 365 days in a year). Id. at 72,276 & n.5. By the comment deadline of March 2, 2020, the BOP received 74 comments, and after considering those, it promulgated a final rule, effective March 14, 2022, formally implementing the proposed methodology. Good Conduct Time Credit Under the First Step Act , 87 Fed. Reg. 7,938, 7,938 (Feb. 11, 2022) (codified at 28 C.F.R. pt. 523).

On December 19, 2016, then-thirty-six-year-old Christopher Thieme began serving a 210-month sentence for the use of interstate commerce facilities in the commission of murder-for-hire, see 18 U.S.C. § 1958(a), and attempted kidnapping, see id. § 1201(a), (d). When Thieme was sentenced, the maximum good conduct time credit available to him was 823 days. But on April 25, 2020, after the enactment of the First Step Act and the publication of the BOP’s notice of Page 8proposed rulemaking, the BOP recalculated Thieme’s potential credits and determined that he would be eligible for 944 days of good conduct time credit. That revised calculation prorated the good conduct time credit for the last six months of Thieme's sentence, and, after rounding down fractions of a day, set the credit at 26 days for that period. Cf. Good Conduct Time Credit Under the First Step Act , 87 Fed. Reg. at 7,940 n.3 (“[I]t is the Bureau’s convention to round down any partial day of [good conduct time credit] to the nearest whole number.”).

Thieme disagreed with the proration of the good conduct time credit for the final six months of his sentence. Cf. Good Conduct Time Credit Under the First Step Act , 84 Fed. Reg. at 72,275 (considering but rejecting an interpretation of the First Step Act amendments under which “an inmate [would] earn[] 54 days of credit each year, and , on the first day of the last chronological year of the service of his/her sentence, earn[] another 54 days”). Without prorating the final six months of his sentence, Thieme would be eligible for 972, not 944, total days of good conduct time credit, resulting in a potential release 28 days earlier than under the BOP’s calculation.

To contest that extended confinement period, Thieme, while incarcerated at Federal Correctional Institution Fort Dix, filed a pro se petition for a writ of habeas corpus under 28 U.S.C. § 2241 with the District Court on October 22, 2020. See Preiser v. Rodriguez , 411 U.S. 475, 487-88 (1973) (explaining that a challenge to good conduct time credits that would 'shorten[] the length of . . . confinement, rather than require[] immediate discharge from that confinement,” would be within 'the core of habeas corpus in attacking the very duration of . . . physical confinement itself”); see also 28 U.S.C. § 2241(c)(3) (allowing persons “in custody in violation of the Constitution or laws or treaties of the United States” to petition for a writ of habeas corpus under § 2241). His challenge was primarily to the BOP’s interpretation of the First Step Act amendments that resulted in a proration of the Page 9good conduct time credits for the last six months of his sentence. He amplified his argument by asserting that the BOP's interpretation violated his due process rights and the Administrative Procedure Act, codified as amended at 5 U.S.C. §§ 551-559, 701-706. He further asserted that a court applying Chevron deference to the BOP's interpretation would offend separation of powers principles.

The District Court denied Thieme's petition. Thieme v. Ortiz , 2023 WL 2706757, at *1 (D.N.J. Mar. 30, 2023). It rejected Thieme’s APA claims on the ground that the Sentencing Reform Act of 1984 precludes challenges to agency “determination[s], decision[s], or order[s]” related to the BOP’s individualized calculations of a prisoner’s potential release date. Id. at *2 (quoting 18 U.S.C. § 3625). And as to Thieme’s remaining challenge to the BOP’s construction of the statute, the District Court explained that “the plain language of § 3624(b)(1) clearly and unambiguously allows for proration[.]” Id. at *5. As an alternative to its plain-language rationale, the District Court relied on Chevron deference to uphold the BOP’s interpretation of the revised statute. Id.

Through a timely notice of appeal, Thieme invoked this Court's appellate jurisdiction. See 28 U.S.C. § 1291. In a thoughtful, well-composed pro se brief, he argued that the District Court erred in several respects by upholding the BOP’s proration of his good conduct time credit.⁴ After the initial Page 10briefing closed, this Court entered an order appointing amicus curiae counsel to further address those and related issues, 5 and permitting amicus and the Government to file supplemental briefs.⁶

Page 11Section 2241 allows habeas petitions by persons 'in custody in violation of the Constitution or laws or treaties of the United States.' 28 U.S.C. § 2241(c)(3). Here, Thieme argues that he will be held in custody in violation of federal law based on the BOP's reading of the statute, 18 U.S.C. § 3624(b)(1), as amended by the First Step Act. His primary challenge is to the District Court's upholding of the BOP's interpretation of the statute, which prorates good conduct time credits for a partial year. Thieme contests that construction of the statute and contends that the good conduct time credits for the final six months of his sentence should not be subject to proration, such that he would be eligible for good conduct time credit for 28 additional days. As adjuncts to his statutory interpretation argument, Thieme also raises other challenges to the District Court’s ruling: he argues that proration of his final six months of good conduct time credits violates his constitutional due process rights, the Administrative Procedure Act, and, if the BOP's interpretation receives Chevron deference, then separation of powers principles as well.⁷

Thieme’s adjunct arguments are nonstarters. First, he does not articulate a viable due process claim. The most prominent cases he cites Wolff v. McDonnell , 418 U.S. 539 (1974); Young v. Kann , 926 F.2d 1396 (3d Cir. 1991); and Queen v. Miner , 530 F.3d 253 (3d Cir. 2008) - are procedural due process challenges to BOP adjudications that denied good conduct time credits to individual prisoners based on their own conduct.⁸ See Wolff , 418 U.S. at 543; Young , 926 F.2d at 1397; Queen , 530 F.3d at 254 n.2. Yet Thieme's due process challenge targets the BOP’s rulemaking – not an alleged lack of adjudicative procedure. Unlike adjudication, rulemaking does not implicate procedural due process. See Vt. Yankee Nuclear Power Corp. v. Nat. Res. Def. Council, Inc. , 435 U.S. 519, 542 n.16 (1978) (explaining that a “rulemaking Page 13proceeding in its purest form” does not constitutionally require “additional procedural devices”); compare Londoner v. City & County of Denver , 210 U.S. 373, 385-86 (1908) (evaluating a due process challenge to an adjudicatory proceeding), with BiMetallic Inv. Co. v. State Bd. of Equalization , 239 U.S. 441, 445–46 (1915) (evaluating a due process challenge to rulemaking). Accordingly, without challenging adjudicative shortcomings, Thieme does not have a viable procedural due process claim.

Thieme gets further with his APA claims, but they are still not successful. The text of the APA allows challenges to agency action to be brought in habeas petitions.⁵ U.S.C. § 703; see also Gardner v. Grandolsky , 585 F.3d 786, 788, 790–93 (3d Cir. 2009) (deciding an APA claim against a BOP regulation within a habeas petition). But the writ of habeas corpus is a means of challenging “unlawful executive detention” for which the “typical remedy . . . is . . . release.” Munaf v. Geren , 553 U.S. 674, 693 (2008). Thus, for an APA claim to be brought in habeas, it must have some relationship to the prisoner’s release. Thieme satisfies that nexus requirement because his APA claims challenge the proration and the loss of a potential 28 days of good conduct time credits.

As to the merits of his APA claims, the APA allows challenges to “final agency action,” 5 U.S.C. § 704, with the APA defining the sub-term ‘agency action’ to include agency rules and orders, id. § 701(b)(2); id. § 551(13) (defining ‘agency action’ to “include[] the whole or a part of an agency rule, order, license, sanction, relief, or the equivalent or denial thereof, or failure to act'). That finality principle prevents Thieme from challenging the BOP’s rule, codified in regulation at 28 C.F.R. pt. 523, of its interpretation of the First Step Act amendments. When Thieme filed his habeas petition on October 22, 2020, the BOP had previously, on December 31, 2019, proposed its new rule, and the comment period had closed on March 2, 2020. See Good Conduct Time Page 14Credit Under the First Step Act , 84 Fed. Reg. at 72,274 (directing comments to be submitted by March 2, 2020). But the BOP had not yet issued a final rule. See Good Conduct Time Credit Under the First Step Act , 87 Fed. Reg. at 7,938 (Feb. 11, 2022). And thus, Thieme's APA challenge to the regulation was premature and validly rejected. See Corner Post, Inc. v. Bd. of Governors of Fed. Rsrv. Sys. , 603 U.S. 799, 808 (2024) (explaining that “§ 704’s finality requirement . . . is a 'necessary, but not by itself . . . sufficient, ground for stating a claim under the APA’” (quoting Herr v. U.S. Forest Serv. , 803 F.3d 809, 819 (6th Cir. 2015)) (ellipses in original)); Bennett v. Spear , 520 U.S. 154, 177–78 (1997) (explaining the conditions for agency action to be considered 'final' and therefore reviewable under the APA). The finality principle, however, does not prevent Thieme from challenging the BOP’s recalculation of his earliest possible release date. Such a determination qualifies as an agency order, 9 and the BOP made that determination using its new methodology on April 25, 2020, before Thieme filed suit.

Page 15Although the APA itself does not present a barrier to Thieme's proceeding with an APA challenge to the BOP's determination of his release date, the Sentencing Reform Act of 1984 does. Part of that legislation expressly exempted several provisions of the APA from applying to a subchapter within Title 18 of the United States Code:

The provisions of sections 554 and 555 and 701 through 706 of title 5, United States Code, do not apply to the making of any determination, decision, or order under this subchapter.

Pub. L. No. 98-473, tit. II, § 212(a)(2), 98 Stat. 2010 (1984) (codified at 18 U.S.C. § 3625). One of the exempted APA sections, 5 U.S.C. § 706, is the basis for Thieme’s APA claim. And the referenced 'subchapter' includes the challenged statutory provision, 18 U.S.C. § 3624(b)(1), which governs the calculation of good conduct time credit. See Reeb v. Thomas , 636 F.3d 1224, 1227 (9th Cir. 2011) (“The plain language of [18 U.S.C. § 3625] specifies that the judicial review provisions of the APA, 5 U.S.C. §§ 701-706, do not apply to 'any determination, decision, or order’ made pursuant to 18 U.S.C. §§ 3621–3624.”); Richmond v. Scibana , 387 F.3d 602, 605 (7th Cir. 2004) (explaining that inmate placement decisions governed by 18 U.S.C. §§ 3621(a) and 3624(c) are “not open to challenge under the APA” in light of § 3625). Consequently, Thieme cannot bring an APA challenge to the BOP’s calculation of his specific release date. See Murray v. Bledsoe , 650 F.3d 246, 247 n.1 (3d Cir. 2011) (per curiam) (explaining “that the APA’s provisions for judicial review of administrative agency decisions . . . do not apply to decisions made under 18 U.S.C. §§ 3621–26” (citing 18 U.S.C. § 3625)); see also Standifer v. Ledezma , 653 F.3d 1276, 1279 n.3 (10th Cir. 2011) (recognizing that § 3625 “prohibits judicial review under the APA”).

Page 16Thieme’s additional constitutional argument – a separationof-powers challenge to Chevron deference - is directed at the District Court’s reliance on Chevron as an alternative ground for its ruling. But after the District Court issued that decision, the Supreme Court abrogated Chevron deference, see Loper Bright Enters. v. Raimondo , 603 U.S. 369, 412 (2024) (overruling Chevron, U.S.A., Inc. v. Nat. Res. Def. Council, Inc. , 467 U.S. 837 (1984)), and without Chevron deference, the District Court’s ruling depends wholly on the meaning of the First Step Act amendments.

As far as Thieme’s challenge to the BOP’s interpretation of § 3624(b)(1), the strongest argument against the proration of good conduct time credit is that the First Step Act deleted the term ‘prorated’ from the statute. The significance of a deletion of statutory text is informed by the rule against superfluity. See Hayes v. Harvey , 903 F.3d 32, 42 (3d Cir. 2018) (recognizing that the presumption that Congress “intends [its amendments] to have real and substantial effect” is a corollary of the canon against superfluity (quoting Ross v. Blake , 578 U.S. 632, 641– 42 (2016))). Under that canon, “every word in a statute should be given effect.” United States v. Weiss , 52 F.4th 546, 552 (3d Cir. 2022) (citing Nat'l Ass'n of Mfrs. v. Dep't of Def. , 583 U.S. 109, 128–29 (2018)). Thus, if text is deleted from a statute, the statute will not ordinarily have the same meaning as it had with the text included. See Pierce County v. Guillen , 537 U.S. 129, 145 (2003) (rejecting an interpretation of a statute that “would render [an amendment] . . . an exercise in futility,” as a “reading [that] gives [an] amendment no ‘real and substantial effect’ . . . cannot be the proper understanding of the statute” (quoting Stone v. INS , 514 U.S. 386, 397 (1995))). But the First Step Act’s revisions were not entirely deletions; they also substituted the phrase ‘for each year’ in place of ‘at the end of each year.’ First Step Act of 2018, Pub. L. No. 115391, tit. I, § 102(b)(1), 132 Stat. 5194, 5210 (codified atPage 17 18 U.S.C. § 3624(b)(1)). And the words ‘for each,’ which are not statutorily defined or recognized terms of art, 10 have a common and ordinary meaning synonymous with the word ‘per.’ See Per , Merriam-Webster's Collegiate Dictionary 918 (11th ed. 2003) (defining ‘per’ to mean “with respect to every member of a specified group: for each”); Per , Oxford English Dictionary (Aug. 2025) (defining 'per,' '[i]n [its] distributive sense,' to mean '[f]or each' or 'for every').¹¹ That word, when '[u]sed after a statement of number or quantity,' 'express[es] a rate or proportion.' Per , Oxford English Dictionary (Aug. 2025). Thus, although the First Step Act deleted one rate-setting term, ‘prorated,’ it added another, ‘for each,' and that addition was in much closer proximity to ‘54 days’ than ‘prorated’ previously appeared: “up to 54 days for each year of the prisoner’s sentence imposed by the court.” 18 U.S.C. § 3624(b)(1) (emphasis added); see also United States ex rel. Totten v. Bombardier Corp. , 380 F.3d 488, 499 (D.C. Cir. 2004) (Roberts, J.) (inferring that, through the introduction of a phrase in one part of a statute, “Congress was reinforcing – rather than abandoning –” a meaning “that might otherwise have been blurred by the addition of' another provision). From that clause, the revised statute is most naturally read as setting a rate for good conduct time credit at 54 days per year. Thus, despite the First Step Act’s deletion of Page 18the term ‘prorated,’ its other amendments preserve the proration process for the final portion of a year of a prisoner’s sentence.

Resisting that conclusion, amicus argues that in the phrase ‘up to 54 days for each year,’ the word ‘year’ refers to both full years and partial years. It is true that in addition to the ordinary and common meaning of 'year' as full year, 12 the term 'year' can sometimes mean partial year, such as in the phrase ‘school year.’ But context informs statutory interpretation, see City & County of San Francisco v. EPA , 604 U.S. 334, 350 (2025), and the phrase ‘up to 54 days for each year,’ sets the rate at which good conduct time credits accrue. In the rate-setting context, there is real value in using a constant as the denominator. Moreover, the object of statutory construction is to interpret a statutory provision capable of two distinct meanings so that it has only a single meaning – not to preserve both meanings and apply the one that better fits the context of a particular application of the statute. See Loper Bright , 603 U.S. at 400 (explaining that a statutory term “no matter how impenetrable . . . must[] have a single , best meaning' (emphasis added)). Yet under amicus ’s interpretation, the term 'year' would mean 'full year' for the first 17 years of his sentence but then ‘partial year’ for the last six months of his sentence. That approach does not work in the rate-setting context, and more problematically, by attempting to preserve both potential meanings of a statutory provision, it is not a permissible mode of statutory interpretation.

As a final attack, amicus invokes the rule of lenity. That rule applies only to penal statutes, and although the Supreme Court has not determined whether the challenged statute, 18 U.S.C. § 3624(b)(1), is penal, at least one Circuit has Page 19concluded that the pre-First Step Act version of the statute was not penal. Compare Barber , 560 U.S. at 488 (assuming, “for present purposes” and without deciding, “that § 3624(b) can be construed as imposing a criminal penalty' and therefore reserving the question of whether § 3624(b) can be classified as ‘penal’ for purposes of triggering the rule of lenity), with Sash v. Zenk , 428 F.3d 132, 135 (2d Cir. 2005) (Sotomayor, J.) (concluding that § 3624(b) is non-penal). But even if § 3624(b)(1) qualified as penal, the rule of lenity would not automatically apply; rather, it applies only when there is a 'grievous ambiguity.' Barber , 560 U.S. at 488 ('[T]he rule of lenity only applies if, after considering text, structure, history, and purpose, there remains a ‘grievous ambiguity or uncertainty in the statute,' such that the Court must simply 'guess as to what Congress intended.'' (internal citations omitted) (first quoting Muscarello v. United States , 524 U.S. 125, 139 (1998); and then quoting Bifulco v. United States , 447 U.S. 381, 387 (1980))). And there is no such ambiguity here. As explained above, the natural reading of the statute is that good conduct time credits accrue at the rate of 54 days per year and credit for partial years of confinement are determined on a prorated basis.

For the foregoing reasons, we will affirm the judgment of the District Court.