We hold that Albaadani has not waived his procedural-reasonableness argument and that "the record does not indicate that a ‘reasonable observer’ would have concluded that there was even the appearance that [Albaadani's national origin or gender] played a role in the district court's sentencing determination." See UnitedStates v. Hughes , 283 Fed.Appx. 345, 355 (6th Cir. 2008) (quoting United States v. Kaba , 480 F.3d 152, 157 (2d Cir. 2007) ).1. Waiver and Forfeiture

, In re Kaitlyn P., 2011 ME 19, ¶¶ 7, 9, 12 A.3d 50.[¶ 20] Butsitsi asks us to adopt the approach enunciated by the Second Circuit in United States v. Kaba, 480 F.3d 152, 156–58 (2d Cir.2007) and United States v. Leung, 40 F.3d 577, 585–86 (2d Cir.1994), which calls for a de novo review of unpreserved claims of judicial bias based upon the defendant's national origin at sentencing. In Kaba and Leung, the Second Circuit reasoned that it was irrational to require defendants to contemporaneously object to the sentencing court's remarks when the remarks were either ambiguous or made in the course of announcing the sentence and doing so could risk upsetting the sentencing judge. Kaba, 480 F.3d at 158 ; Leung, 40 F.3d at 586.

Aine argues, and the government concedes, that because certain statements by the district court at sentencing might appear to have been based on defendant's national origin and alien status, the sentence must be vacated. Reviewing this aspect of the sentence de novo, see United States v. Kaba, 480 F.3d 152, 156-57 (2d Cir. 2007), we agree that such a conclusion is dictated by our precedent. Although Aine has served the custodial portion of his sentence, his case is not moot, see United States v. Key, 602 F.3d 492, 494 (2d Cir. 2010), because there is a "possibility that the district court could impose a reduced term of supervised release" or modify the amount of restitution.

Munafo responds that even the appearance of reliance on an impermissible factor can invalidate a sentence. For that variant of taint, Munafo relies principally on the Second Circuit's decision in United States v. Kaba, 480 F.3d 152, 158 (2d Cir. 2007), which vacated and remanded a sentence that the district court had justified in part as a crime deterrent directed at people of the defendant's national origin. But Kaba-unlike Munafo-had not waived her right to challenge her sentence on appeal, id., and the Second Circuit accordingly did not address whether proof

"It has long been settled in this Circuit that although reference to national origin and naturalized status is permissible during sentencing, it is allowed only so long as it does not become the basis for determining the sentence." United States v. Kaba, 480 F.3d 152, 156 (2d Cir. 2007). We review de novo "whether the district court improperly considered the defendant's national origin."

Rodriguez urges us to craft an exception to the contemporaneous objection rule for objections suggesting that the district judge was either biased or had created the appearance of bias. She relies on the rationale of two cases from the Second Circuit, United States v. Leung, 40 F.3d 577 (2d Cir. 1994). and United States v. Kaba, 480 F.3d 152 (2d Cir. 2007). In Leung the Second Circuit vacated and remanded after the sentencing judge made two remarks that referred to the defendant's ethnic origin and alien status.

Whether a district court improperly considers a defendant's national origin is a question of law, and thus this aspect of a sentencing is reviewed de novo. United States v. Kaba, 480 F.3d 152, 156-57 (2d Cir. 2007). At sentencing here, defendants' national origin was initially raised by defense counsel.

’ ” (citing U.S.S.G. § 5H1.10)); United States v. Kaba, 480 F.3d 152, 156–58 (2nd Cir.2007). The prosecutor's attempt to inject consideration of David's ethnicity and national origin into the determination of David's sentence in order to “send[ ] a message to the Mircronesian community” clearly constituted prosecutorial misconduct.

See Leung, 40 F.3d at 586 ("[W]e reject the view that a defendant's ethnicity or nationality may legitimately be taken into account in selecting a particular sentence to achieve the general goal of deterrence."); United States v. Trujillo–Castillon, 692 F.3d 575, 579 (7th Cir.2012) ("The [United States Sentencing Guidelines] make clear that race ... [and] national origin ... ‘are not relevant in the determination of a sentence.’ " (citing U.S.S.G. § 5H1.10 )); United States v. Kaba, 480 F.3d 152, 156–58 (2nd Cir.2007). The prosecutor's attempt to inject consideration of David's ethnicity and national origin into the determination of David's sentence in order to "send[ ] a message to the Mircronesian community" clearly constituted prosecutorial misconduct.

Oladimeji also argues that he is entitled to be resentenced because the District Court impermissibly based its sentence on his nationality and immigration status. See United States v. Kaba, 480 F.3d 152, 156 (2d Cir. 2007). We disagree.