The Supreme Court ruled 8, 1 in Hunter v. United States that appeal waivers in criminal plea deals are generally enforceable, but not when enforcing them would produce a "miscarriage of justice." Justice Amy Coney Barrett joined the majority in full, then wrote a separate concurrence aimed squarely at the lone dissenter: Justice Clarence Thomas.
The split between two of the Court's most prominent conservative voices drew immediate attention. Barrett's concurrence did not merely restate the majority's reasoning. She engaged Thomas's dissent point by point, arguing that longstanding legal principles, not judicial invention, support the idea that some rights cannot be bargained away, even by a defendant who signs on the dotted line.
The case centers on Munson Hunter III, who pleaded guilty to a fraud charge as part of a deal that saw nine other counts dropped. Hunter agreed to waive his right to appeal his sentence. But at sentencing, the judge imposed a condition Hunter had not anticipated: a requirement that he take any mental health medications prescribed by his doctor while on supervised release. Hunter argued the forced-medication condition violated his constitutional right to refuse unwanted medical treatment, and sought to challenge it despite the waiver he had signed.
Justice Elena Kagan authored the majority opinion, which established a nationwide standard for when appeal waivers can be overridden. The Court held that such waivers are "generally enforceable" but set what it called a "deliberately high bar": a defendant may appeal despite a waiver if enforcing it would result in a "miscarriage of justice." The ruling resolved what the Court described as a "longstanding divide among federal appeals courts over how strictly to enforce plea deal waivers."
The Court did not decide whether Hunter's forced-medication claim actually meets that threshold. Instead, it remanded the case to the Fifth Circuit Court of Appeals to apply the new standard and make that determination.
That procedural move matters. It means the justices set the rule but left the hardest factual question for the lower court, a common approach, but one that guarantees further litigation. The vast majority of criminal cases are resolved without trial, as Newsweek noted, which means the enforceability of plea deal waivers touches an enormous share of the federal criminal docket.
Barrett's concurrence went beyond a polite "I agree but want to add a thought." She directly rejected Thomas's argument that the majority had invented a new rule without legal grounding. Courts, Barrett wrote, have long recognized limits on what defendants can waive, even voluntarily.
Barrett stated:
"There are some rights that a criminal defendant 'cannot be deprived of even with his own consent.'"
The interior quotation suggests Barrett was drawing on established precedent, though the specific source of the quoted phrase was not identified in the Court's published materials as reported. Her broader point was clear: the "miscarriage of justice" exception fits within longstanding legal principles, not outside them.
Barrett also argued that enforcing a waiver under circumstances like Hunter's, where the sentencing condition arguably infringes a constitutional right the defendant never contemplated giving up, would "irreparably discredit" the judicial process. That phrase captures the heart of her disagreement with Thomas. For Barrett, a plea deal waiver is not a blank check that strips a defendant of every possible objection, no matter how fundamental.
The exchange is notable because Barrett and Thomas typically vote together on major cases. This term alone has featured a string of consequential Supreme Court decisions in which the conservative justices have not always lined up as expected.
Thomas wrote a lengthy dissent, the only justice to break from the 8, 1 majority. His position was straightforward: a deal is a deal. If a defendant knowingly and voluntarily waives the right to appeal, courts should hold him to that bargain. Period.
Thomas wrote:
"Like many constitutional and statutory rights, the right to appeal can be waived...and once that choice is finally made, the defendant is bound by the decision."
He warned that the majority's new "miscarriage of justice" standard would open the door to a wave of challenges from defendants looking to escape the terms of their plea agreements. In Thomas's view, the exception the Court carved out has no firm legal basis and will invite exactly the kind of litigation it claims to limit.
Thomas has not been shy about standing alone this term. He was also the sole voice rebuking the Court for declining to hear Florida's case against states licensing illegal immigrant truckers, another instance where he argued the majority ducked a question it should have answered.
Thomas's lone dissent in Hunter follows a pattern. Earlier this term, the Supreme Court ruled 8, 1 to uphold a 1994 federal law banning firearm possession for individuals under domestic violence restraining orders. Thomas was again the sole dissenter, arguing the law "strips an individual of his ability to possess firearms and ammunition without any due process" and that no historical regulation justified the statute.
That case involved a Texas man, Zackey Rahimi, who was accused of hitting his girlfriend and was linked to five shootings over two months while under a restraining order. Chief Justice Roberts wrote the majority opinion, grounding the decision in historical tradition. Thomas rejected that reasoning entirely.
Two 8, 1 splits in the same term, both with Thomas alone, raise questions about whether the Court's conservative wing is fracturing on criminal justice and individual rights issues, or whether Thomas is simply more willing than his colleagues to follow his originalist framework to its logical endpoint, even when the result is politically uncomfortable.
The broader dynamics of the Court have drawn scrutiny from multiple directions. A recent tariff ruling also highlighted tensions among the conservative justices, with Barrett and Gorsuch drawing criticism for their positions.
The practical effect of Hunter v. United States is significant but bounded. The Court affirmed that plea deal waivers remain enforceable as a general matter. Prosecutors can still negotiate waivers, and defendants who sign them will be held to their word in the vast majority of cases.
But the new "miscarriage of justice" standard, described by the Court as a "deliberately high bar", creates a narrow escape hatch. Defendants who can show that enforcing a waiver would produce a result so unjust that it discredits the judicial system itself now have a path to appeal, even if they agreed not to.
How the Fifth Circuit applies that standard to Hunter's forced-medication condition will be closely watched. If the lower court finds that compelling a defendant to take psychiatric medication as a condition of supervised release crosses the "miscarriage of justice" line, it could set a precedent affecting sentencing conditions nationwide. If it does not, the standard may prove more symbolic than operational.
The Court's decision to send cases back to lower courts rather than resolve the hardest questions itself has become a recurring feature of this term. It preserves flexibility, but it also delays clarity for defendants, prosecutors, and judges who need to know where the lines are.
Barrett's willingness to write separately and confront Thomas head-on is worth watching. It is not a break with conservative jurisprudence. Barrett joined the majority in full and framed her concurrence as a defense of existing legal principles, not an expansion of them. She argued that recognizing limits on waiver is not judicial activism, it is fidelity to a tradition that predates the Constitution itself.
Thomas, for his part, made the case that fidelity to contract principles and individual autonomy should mean honoring a defendant's voluntary choice, even when the consequences are harsh. His concern about a flood of new challenges is not hypothetical. Federal courts already face enormous caseloads, and any new avenue for post-plea litigation will add to the burden.
Both positions reflect genuine conservative commitments, to individual liberty, to the rule of law, and to judicial restraint. The disagreement is over which commitment controls when they collide. That is a healthy debate, and one the Court's conservative members are clearly willing to have in public.
The Court's other landmark rulings this term have shown similar internal tensions, with justices splitting along lines that do not always match the neat ideological categories commentators prefer.
When two principled jurists disagree this sharply in writing, it is not a crisis. It is the system working. The real test is whether the standard they set holds up under the weight of the cases that will follow.