United States v. Robert McNabb, 958 F.3d 338

Defendant Robert McNabb pleaded guilty to being a felon in possession of a firearm and signed a plea agreement that included an appeal waiver and a promise by the government to “not oppose” an acceptance-of-responsibility reduction.
The original PSR recommended the acceptance reduction; the government filed an objection seeking a two-level obstruction-of-justice enhancement under U.S.S.G. § 3C1.1 based on pre-plea conduct (threatening a witness and an agent; letters about making meth).
Probation issued a revised PSR recommending the obstruction enhancement and withdrawing the acceptance recommendation; the district court adopted the revised PSR, applied the obstruction enhancement, and denied the acceptance reduction.
McNabb did not raise a breach-of-plea-agreement claim in the district court; he appealed arguing the government breached its promise by effectively opposing the acceptance reduction via its obstruction submission and by relying on pre-plea conduct.
The panel treated McNabb’s claim under plain-error review (because he failed to present it below), found the breach claim to be a close question under controlling precedent, and concluded the error was not obvious; therefore the appeal waiver remained enforceable and the sentencing challenges were dismissed.

Issue	Plaintiff's Argument	Defendant's Argument	Held
Whether the government breached the plea agreement by opposing an acceptance-of-responsibility reduction through seeking an obstruction enhancement based on pre-plea conduct	McNabb: “Not oppose” was limited to conduct after the plea; using pre-plea conduct to obtain obstruction breached the promise	Government: It promised only to “not oppose,” reserved the right to present and dispute facts and seek enhancements; seeking obstruction was not inconsistent	Court: Close question; under plain-error review error was not obvious. Did not find an obvious breach.
Whether a breach would invalidate McNabb’s appellate waiver and allow his sentencing challenges	McNabb: A government breach would free him from his waiver and permit review	Government: No breach; waiver remains enforceable	Court: Because no plain/obvious breach shown, Gonzalez-based waiver doctrine applies; appeal dismissed.

United States v. Gonzalez, 309 F.3d 882 (5th Cir. 2002) (government breach of plea agreement can void a defendant’s appeal waiver)
Puckett v. United States, 556 U.S. 129 (2009) (plain-error review requires an obvious/clear error; close calls fail)
United States v. Cluff, 857 F.3d 292 (5th Cir. 2017) (government may seek obstruction enhancement despite promising not to oppose acceptance credit in plea agreement)
United States v. Juarez-Duarte, 513 F.3d 204 (5th Cir. 2008) (obstruction enhancement ordinarily indicates lack of acceptance of responsibility)
United States v. Munoz, 408 F.3d 222 (5th Cir. 2005) (distinguishing cases where government agreed to a defendant’s specified total offense level and then sought enhancements)
United States v. Rosales, [citation="612 F. App'x 778"] (5th Cir. 2015) (per curiam) (no obvious error when government said “not to oppose” acceptance credit but advocated obstruction enhancement and was silent at sentencing)