SCOTUS: Appeal Waivers Resulting in Miscarriage of Justice Are Unenforceable

In Hunter v. United States, 608 U.S. ____ (2026), the U.S. Supreme Court held that an agreement not to appeal a sentence is unenforceable when it would result in a “miscarriage of justice,” which is an egregious error that would bring the judicial system into disrepute. 

Facts of the Case

Petitioner Munson Hunter III was charged with 10 counts of bank and wire fraud for a years-long scheme costing various financial institutions about half a million dollars. He entered into a written plea agreement with the Government under which he pleaded guilty to one count of aiding and abetting wire fraud in exchange for dismissal of the remaining nine charges and a promise not to prosecute him for the described conduct in the future.

The agreement included an appeal waiver under which Hunter waived the right to appeal his conviction and sentence, except that he did not waive the right to raise a claim of ineffective assistance of counsel. The agreement further provided that “any modification” of its terms “must be in writing and signed by all parties.” The District Court accepted the plea after deeming it knowing and voluntary.

At sentencing, the Probation Office recommended that as a condition of supervised release Hunter be required to participate in a mental-health treatment program and take all mental-health medications prescribed by his treating physician. Hunter objected to the mandatory-medication part of that condition. The District Court told Hunter that if “the treatment provider prescribes drugs, you should take them,” while also telling Hunter that he could “address” any future dispute about medication “to the probation officer” or, if needed, “to me.” The District Court then imposed a sentence of 51 months in prison followed by three years of supervised release, including the contested medication condition. At the close of the hearing, the court told Hunter: “All right. You have a right to appeal. If you wish to appeal, [your trial counsel] will continue to represent you.” When asked if either party wished to say anything else, Hunter’s lawyer said “Nothing from the defense,” and the prosecutor replied: “Your Honor, I believe—well, no. I—no.”

Hunter appealed, challenging the mandatory-medication condition as infringing on his “fundamental due process liberty interest in being free of unwanted mental health medication.” The Government sought dismissal based on the appeal waiver. Hunter acknowledged he had knowingly and voluntarily signed the waiver but argued that an appeal waiver is unenforceable when the disputed aspect of a sentence violates a fundamental constitutional right, and alternatively that the District Court’s statement at sentencing about appeal rights, along with the prosecutor’s failure to object, voided the waiver.

The Fifth Circuit Court of Appeals dismissed the appeal, holding that the District Court’s misstatement “did not impact the validity of the appeal waiver” and that under Circuit precedent the “general rule” that appeal waivers are enforceable has only two exceptions: when the waiver was tainted by ineffective assistance of counsel and when the sentence exceeded the statutory maximum. Because neither exception applied, the Fifth Circuit held that Hunter’s appeal could not go forward.

Supreme Court’s Decision

The Supreme Court reversed by a vote of 8-1. “We principally hold that an agreement not to appeal a sentence is unenforceable when it would result in a miscarriage of justice—meaning, when it would leave in place the kind of egregious error that would bring the judicial system into disrepute,” Justice Elena Kagan wrote on behalf of the Court.

In reaching its decision, the Supreme Court declined to adopt the extreme positions adopted by the government and the appeals court. The justices rejected the government’s position that a knowing, voluntary waiver isalwaysenforceable, and also rejected the Fifth Circuit’s holding that a waiver failsonlywhen the sentence exceeds the statutory maximum. Instead, it adopted the stance taken by most courts: declining to enforce appeal waivers when doing so would produce a “miscarriage of justice.”

As Justice Kagan explained, the standard reflects the role of the judiciary in approving and implementing appeal waivers. “ [T]he standard for enforcing appeal waivers implicates the interests not only of the agreement’s parties, but also of the judiciary,” she wrote. “If a court always carries out those waivers—no matter the kind or degree of error tainting a sentence—the judicial system’s integrity may come into question.”

Justice Kagan went on to explain why the Government’s and the Fifth Circuit’s proposed rule can’t be the right one. She wrote:

Suppose, for example, that a judge sentences a misdemeanant to life in prison, when the applicable law caps a prison term at one year. If an appellate court had to dismiss the resulting appeal, it would call into doubt the judicial system’s very attachment to law. But so too would a dismissal in certain other situations, which fall outside both the Government’s and the Fifth Circuit’s rules. Consider some examples offered at oral argument in this case. If, say, the sentencing judge was biased against individuals of one race or religion, and unconstitutionally considered that factor in imposing a sentence. Or if the judge (as in an actual case) imposed as a condition of supervised release that the defendant not become pregnant. Or if the judge, to use a variation on Mezzanatto’s absurdity, “let an orangutan pick a sentence out of a hat.” Those sentences would likewise impugn the judiciary’s integrity if an appeal waiver compelled them to stand. However certain the parties’ agreement, the courts are too enmeshed in its approval and implementation to escape responsibility for such results.

The Supreme Court emphasized that the miscarriage-of-justice standard sets a high bar, and a waiver may be set aside only if the sentence is marred by the kind of egregious error that would bring the judicial system into disrepute. “The error must be obvious—not one a judge could reasonably make,” Justice Kagan explained. “And it must be of the type that would undermine public confidence in the judiciary.”

While emphasizing that standard-fare errors in misapplying sentencing law can’t cancel an appeal waiver, the Court noted that “a high bar is not the same as an insurmountable one.” Instead, the miscarriage-of-justice limit “offers a safety valve for extreme cases when the justice system’s basic integrity is at stake.”

Finally, the Court acknowledged that the nature of the miscarriage-of-justice limit precluded any attempt to list all the situations in which it will overcome an appeal waiver. Nonetheless, it did list a few examples of the kinds of errors that would bring the judiciary into disrepute may provide guidance to lower courts: a sentence exceeding what the relevant statute allows; a sentence infected with a blatant constitutional error, such as when a judge takes account of a constitutionally impermissible factor (like race) or imposes a constitutionally infirm condition of supervised release; and a sentence imposed without some minimum of civilized procedure.