PUBLISH
UNITED STATES COURT OF APPEALS
FOR THE TENTH CIRCUIT

________________ _________________ UNITED STATES OF AMERICA, Plaintiff - Appellee,

v. CONNER LEE POLK, Defendant - Appellant. No. 22-5037

________________ _________________ Appeal from the United States District Court for the Northern District of Oklahoma (D.C. No. 4:21-CR-00294-GKF-1)

________________ _________________ Andrew M. Casey of Hendrick, Casey, Hutter, PLLC, Oklahoma City, Oklahoma (Shannon M. McMurray of Viridian Legal Services, PLLC, Tulsa, Oklahoma, with him on the briefs), for Defendant-Appellant. Leena Alam, Assistant United States Atto rney (Clinton J. Johnson, United States Attorney, Chantelle Dial, Assist ant United States Attorney, on the briefs), United States Attorney’s Office, Northern District of Oklahoma, Tulsa, Oklahoma, for PlaintiffAppellee.

________________ _________________ Before MORITZ , SEYMOUR , and EID , Circuit Judges.

________________ _________________ MORITZ , Circuit Judge.

________________ _________________ Conner Lee Polk appeals his four-year prison sentence under the Assimilative Crimes Act (ACA), 18 U.S.C. § 13, for co mmitting a state-law offense on an Indian FILED United States Court of Appeals Tenth Circuit 

### March 13, 2023 Christopher M. Wolpert Clerk of Court Appellate Case: 22-5037 Document: 010110825224 Date Filed: 03/13/2023 Page: 12 reservation in Oklahoma. Polk argues that the district court s hould have considered imposing a shorter prison term under an Ok lahoma statute that permits a departure from a mandatory minimum sent ence in certain circumstances . Because this state law conflicts with federal senten cing policy, the district cour t properly declined to apply it, and we affirm Polk’s sentence. Background In December 2019, Polk crashed his pickup truck into two cars while intoxicated, seriously injuring occupants in one of the ve hicles. Because this conduct occurred on an Indian reservation and Polk is an Indian, a federal prosecution ensued under the ACA. As explained in more detail later, the ACA appl ies to acts committed on an Indian reservation that are crimes in the st ate within which the reservation is located—here, Oklahoma—but are not ot herwise crimes under federal law. See § 13(a). The government charged Polk un der the ACA with an Oklahoma DUI offense that carries a mandato ry prison sentence of at l east 4 years and at most 20
years. See Okla. Stat. tit. 47, § 11-904(B)(1). He eventually pleaded guilty to that offense. 1 Despite the mandatory minimum applicable to his offense, Polk at sentencing requested a prison term of less than four years. For su pport, he cited Oklahoma’s “safety-valve” law, which allows state-c ourt judges in certain circumstances to

1 Polk also pleaded guilty to an ACA offense for i nvolvement in an accident that damaged a vehicle, see Okla. Stat. tit. 47, § 10-103 , for which he received a concurrent six-month prison sentence. He does not challenge his conviction or sentence for this offense. Appellate Case: 22-5037 Document: 010110825224 Date Filed: 03/13/2023 Page: 23 impose a sentence below a statutory mandatory minimum. See Okla. Stat. tit. 22, § 985.1(A). The district court, however , concluded that it could not apply Oklahoma’s safety-valve law because that provision conflic ts with federal sentencing provisions that permit federal courts to depart from statutory mandatory minimums only in two limited circumstances, neither of which exists here. See 18 U.S.C. § 3553(e)–(f). Given this conf lict, the district court sent enced Polk to the four-year mandatory minimum prison term. Analysis Polk appeals his sentence, arguing that th e district court erred in declining to apply Oklahoma’s safety-valve law to consid er whether he qualified for a departure below the four-year mandatory minimum. That argument hinges on whether the district court properly interpreted the ACA, the relevant federal sentencing provisions, and Oklahoma’s safety-valve law. We review those legal determinations de novo. See United States v. Chapman , 839 F.3d 1232, 12 41 (10th Cir. 2016)

. As relevant here, the ACA provides fe deral jurisdiction over certain criminal acts committed on Indian reservations. 2 United States v. Garcia , 893 F.2d 250, 253

2 By its terms, the ACA applies only to crimes committed on federal enclaves—“areas where states have ceded jurisdiction over land within their borders to Congress, such as military bases, federal facilities , and national parks and forests.” United States v. Harris , 10 F.4th 1005, 1010 (10th Cir. 2021). It applies to crimes on Indian reservations by way of 18 U.S.C. § 1152, which extends federal-enclave law to Indian country, see United States v. Langford , 641 F.3d 1195, 1197 (10th Cir. 2011) (explaining that “in conjunction,” ACA and § 11 52 “(1) assimilate state criminal law into federal la w” for acts committed on federa l enclaves and “(2) apply these assimilated state crimes to acts committed in Indian country”). Appellate Case: 22-5037 Document: 010110825224 Date Filed: 03/13/2023 Page: 34 (10th Cir. 1989). When such acts occur, they ar e often prohibited by specific federal criminal statutes. For in stance, the Major Crimes Act, 18 U.S.C. § 1153(a), proscribes a list of severe offenses, such as murder and kidnapping, that are federal crimes when committed by Indians in Indian country. But sometime s, as is the case here, no particular federal st atute covers the defendant’s conduct, meaning it would not otherwise be a federal crime. United States v. Jones , 921 F.3d 932, 935 (10th Cir. 2019). In that event, the ACA steps in and generates a federal of fense using the laws of the state in which the rele vant reservation is located. See id. More precisely, it allows federal courts to “ borrow [the relevant crime] from preexisting state law,” thereby creating an applicable federal offense to fill the gap in the U.S. Code. United States v. Christie , 717 F.3d 1156, 1170 (10th Cir. 2013); cf. also United States v.
Martinez , 1 F.4th 788, 790 (10th Cir. 2021) (explaining that “[ t]he assimilated state offense becomes a federal offens e punishable under federal law”), cert. denied , 142 S. Ct. 1373 (2022). Notably, however, the ACA does not re quire federal courts to incorporate

every aspect of state criminal law that may apply to the newly created offense. See Christie , 717 F.3d at 1171–72. To the contrary, it requires only that they ensure the defendant receives a “like puni shment,” § 13(a)—one similar to the punishment he or she would receive in state court. See Christie , 717 F.3d at 1171–72 (emphasizing that “the ACA requires like punishment, not precisely the same punishment”). Typically, this like-punishment standard means that we must apply “any maximum and minimum prison terms pr[e]scribed by st ate law for an assimilated crime.” Id. at Appellate Case: 22-5037 Document: 010110825224 Date Filed: 03/13/2023 Page: 45 1171. But in imposing a sentence between those mandatory values, federal courts need not “duplicate every last nuance of th e sentence that would be imposed in state
court.” Id. at 1172 (quoting Garcia , 893 F.2d at 254). And critic ally, “federal courts

must depart from state [sentencing laws] wh en Congress has expr essed a specific and contrary penal policy.” Id. ; see also United States v. Wood , 386 F.3d 961, 963 (10th Cir. 2004) (“[W]hen sentencing defendants for assimilated crimes, federal courts have consistently declined to assimilate state sentencing laws if such laws conflict with the [United States Sentencing] Gu idelines and their underlying policies.”). Applying this principle, th e district court concluded that it could not sentence Polk under the Oklahoma safety-valve law because that law conflicts with federal sentencing policy, in partic ular 18 U.S.C. § 3553(e) a nd (f). Polk disputes this conclusion, arguing that no such conflict exis ts and that the district court therefore should have incorporated Oklahoma’s safe ty-valve law and considered imposing a prison term of less than four years. But Polk does not meaningfully grapple with the district court’s reasons for finding a conflict. As the district court explained, under § 3553, federal sentencing judges may “depart from a mandatory mini mum sentence only in [two] enumerated, limited circumstances,” neither of which applies here. 3 App. vol. 1, 41; see also United States v. C.D. , 848 F.3d 1286, 1292 & n.5 ( 10th Cir. 2017) (noting that

3 As the district court also noted, the Guidelines simi larly permit such departures only in the two circumst ances outlined in § 3553(e) and (f). See U.S.S.G. §§ 5C1.2, 5K1.1. Appellate Case: 22-5037 Document: 010110825224 Date Filed: 03/13/2023 Page: 56 § 3553 contains the “ only two congressionally-authorized exceptions to a mandatory minimum sentence” (emphasis added)). Speci fically, they may do so only when the defendant (1) provides subs tantial assistance to a cr iminal investigation or prosecution, or (2) is convict ed of certain listed drug o ffenses and satisfies five statutory factors. § 3553(e)–(f). Oklahoma’ s safety-valve law, on the other hand, allows departures from ma ndatory minimums under a broa der set of circumstances.
See Okla. Stat. tit. 22, § 985.1(A) (permi tting departure for certain qualifying offenses when mandatory minimum “is not necessary for the protection of the public,” “would result in subs tantial injustice to the defendant,” or “is not necessary for the protection of the public and the defendant . . . has been accepted” to alternative court, diversion program, or co mmunity sentencing). T hus, as the district court concluded, Oklahoma’s safety-valve law conflicts with federal sentencing policy because it would allow a prison term below the mandatory minimum in circumstances other than those exclusiv ely provided for in § 3553(e) and (f). 4 Polk’s contrary argument does not un dermine this straightforward textual conclusion. He suggests that the district court erred by basing its conclusion that a conflict exists on a determination that the federal safety-valve provision, § 3553(f),

4 This direct tension between what st ate law permits and what federal law forbids answers Polk’s asse rtion, drawn from an analogy to the conflict-preemption doctrine, that two laws do not conflict if they merely “overlap” and that a conflict instead requires that it be “[im]possible to comply with both” laws. Rep. Br. 6 (quoting Kansas v. Garcia , 140 S. Ct. 791, 806 (2020)). This impossibility standard plainly is met here: Both pr ovisions cannot be given eff ect because, as mentioned above, Oklahoma’s safety-valve law allows departures for reasons that would not support a departure under § 3553(e) and (f). Appellate Case: 22-5037 Document: 010110825224 Date Filed: 03/13/2023 Page: 67 “never references” the ACA specifically. Ap lt. Br. 25–26. From that premise, Polk then argues that no language in § 3553(f) shows that Congress intended “to exclude [the ACA] from [federal] safe ty[-]valve consideration.” Re p. Br. 3. But this argument both misunderstands and fails to refute the district c ourt’s conflict analysis. As explained, the district court did not base its conclusion that Oklahoma’s safety-valve law conflicts with § 3553 on Congress’s failu re to mention the ACA in subsection (f) (or subsection (e), for that matter). 5 Instead, it based that c onclusion on the fact that Oklahoma’s safety-valve law would allow departures below the mandatory minimum in circumstances beyond those provided for in § 3553(e) and (f). Nothing about Polk’s § 3553(f) argument disputes this un ambiguous conflict, and this conflict is fatal to Polk’s sentencing challenge. 6 See Christie , 717 F.3d at 1172.
Conclusion In sum, because Oklahoma’s safety-valve law conflicts with federal sentencing

5 To the extent that this failure to mention the ACA in the federal safety-valve provision has any significance , it suggests that Congress did intend to exclude ACA offenses because § 3553(f) specifies that it applies only “in the case of” certain enumerated drug offenses. See Navajo Nation v. Dalley , 896 F.3d 1196, 1213 (10th Cir. 2018) (“[T]he enumeration of certain things in a statute suggests that the legislature had no intent of including things not listed or embraced” (quoting Seneca-Cayuga Tribe of Okla. v. Nat’l Indian Gaming Comm’n , 327 F.3d 1019, 1034 & n.24 (10th Cir. 2003))). 6 Because the relevant statutory langua ge is unambiguous, we do not address Polk’s arguments about legislative history, statutory purpose, and the rule of lenity supporting his position. See In re Geneva Steel Co. , 281 F.3d 1173, 1178 (10th Cir. 2002) (noting that courts must interpre t an unambiguous statut e “according to its plain meaning,” considering legislative hi story and statutory purpose only “[i]f a statute is ambiguous”); United States v. Black , 773 F.3d 1113, 1117 (10th Cir. 2014) (requiring showing of “grievous ambiguity or uncertainty in the statute” to apply rule of lenity (quoting Dean v. United States , 556 U.S. 568, 577 (2009))). Appellate Case: 22-5037 Document: 010110825224 Date Filed: 03/13/2023 Page: 78 policy—specifically, § 3553(e) and (f)—the dist rict court did not err in declining to apply that state law when sentencing Po lk. Instead, the district court properly incorporated only the state-law mandatory minimum applicable to Polk’s crime, thereby providing him with the “like punish ment” the ACA requires. § 13(a). Thus, we affirm Polk’s sentence. Appellate Case: 22-5037 Document: 010110825224 Date Filed: 03/13/2023 Page: 8