Law360 (May 28, 2026, 10:58 AM EDT) -- The U.S. Supreme Court held Thursday that judges lack wide discretion to pare down sentences for criminal defendants under the First Step Act based on questions about the validity of a conviction, shutting the door on a potential wave of postconviction relief petitions, experts said.

The 8-1 decision resolves a circuit split over the scope of factors that judges may consider in granting relief under the federal law, which allows the courts to reduce sentences or grant early release to defendants for "extraordinary and compelling reasons."

The ruling effectively seals a "safety valve" under the First Step Act that judges had been using to grant relief to convicted defendants, "because so many other avenues have been closed off to the" judges, Carissa Byrne Hessick, a professor of criminal law at the University of North Carolina School of Law, told Law360.

"When Congress passed the First Step Act under the first Trump administration, it was a rare moment in the modern criminal justice system that expanded the ability to mitigate punishment," Hessick said. "This is a battle over what the Supreme Court will say about how far Congress has expanded it."

During oral arguments in November, several justices had expressed concerns that a ruling for the defendant bringing the appeal, Joe Fernandez, who was convicted in New York for his role in a 2000 double murder-for-hire, could spur a flood of compassionate release motions from prisoners.

"One animating concern behind ... this decision is that if there aren't procedural limitations on the ability to attack the validity of a conviction, those challenges would be extremely common," Peter Siegal, an appellate partner at Bracewell LLP who has been following the Fernandez case, told Law360.

After Fernandez had served about 11 years in prison, he was ordered by a trial judge to be released in 2022 under the First Step Act. The judge's ruling cited "strong concerns" about the evidence against Fernandez and cited a significant disparity between his sentence and the much shorter sentences of his three co-defendants.

A three-judge panel for the Second Circuit reversed the lower court's ruling in 2023, finding that the judge wrongly considered Fernandez's potential innocence as a factor under the First Step Act and that the disparate sentences for his co-defendants did not qualify as "extraordinary and compelling" absent "unusual circumstances."

In his petition to the Supreme Court, Fernandez argued that the Second Circuit's ruling wrongly limited the "broad discretion" trial judges have under the First Step Act to grant compassionate release and conflicted with decisions from the First and Ninth circuits.

Writing for the majority in Thursday's opinion, Justice Amy Coney Barrett held that the "compassionate release provision" under Title 18 of the U.S. Code, Section 3582, "is not a vehicle for attacking the validity of a conviction."

Chief Justice John Roberts and Justices Clarence Thomas, Samuel Alito, Neil Gorsuch and Brett Kavanaugh joined the opinion.

The majority ruled that prisoners must instead challenge the validity of their convictions under Title 28 of the U.S. Code, Section 2255, which "imposes tight procedural constraints," including a one-year statute of limitations and a bar on relitigating claims, Justice Barrett noted.

"With very narrow exceptions, a prisoner gets only one shot at collateral relief," she wrote. "Claims that have already been raised and rejected on direct review typically cannot be relitigated in §2255 motions."

She added, "Challenging the validity of a conviction through a compassionate release motion circumvents the exacting requirements of §2255."

The majority also determined that the "supposed invalidity of a conviction is not among the 'extraordinary and compelling reasons' that justify compassionate release" under Section 3582, which the First Step Act amended.

Congress has not defined "extraordinary and compelling" in the context of the First Step Act. In rejecting Fernandez's argument, Justice Barrett focused on the "compelling" requirement and found that an "argument that is compelling in one context is not necessarily so in another; the force of an argument depends on what it seeks to justify."

"Section 2255's reticulated scheme bears on this inquiry. A reason is not 'compelling' if Congress has channeled it through the postconviction statutes," she wrote. "Even Fernandez recognizes that an argument may be less compelling if it could have been — and was not — asserted through §2255."

Justice Barrett concluded that "when a prisoner persuades a court that his conviction is invalid, the remedy of a little less prison time does not redress the wrong. If a conviction is invalid, the fitting remedy is to vacate it, as §2255 allows. That §3582 does not offer this remedy is evidence that it is not a suitable vehicle for the claim."

The Supreme Court also held in a 6-3 ruling Thursday in a separate case, Rutherford v. U.S., that the U.S. Sentencing Commission lacked congressionally delegated authority to say that the First Step Act's reductions in mandatory minimums could be part of a prisoner's arguments seeking compassionate release.

"Fernandez and Rutherford together make clear that while compassionate release can encompass a wide array of considerations, it is not a vehicle for second-guessing choices that Congress made," said Siegal at Bracewell.

Fernandez's attorney, Benjamin Gruenstein, told Law360 on Thursday that "while the Supreme Court did not rule in our favor today, we will continue to seek relief for Joe Fernandez, who is serving a life sentence despite the trial judge's strong concern that he is innocent."

The U.S. Department of Justice did not respond to a request for comment.

Justice Ketanji Brown Jackson argued in a dissenting opinion that "Congress designed compassionate release as a tool for preserving a modicum of mercy in an otherwise harsh sentencing system."

She added, "And nothing about the text or history of the compassionate-release provision suggests that Congress meant for this discretionary second-look opportunity to be cabined in the way the majority suggests."

Congress intended for the First Step Act to "preserve some of the traditional discretion afforded to district courts to ensure just treatment of defendants in criminal cases," Justice Jackson contended.

She wrote that the majority opinion "arbitrarily restricts that discretion by grafting an atextual rule" onto the law requiring that challenges to the validity of a conviction be made through habeas relief motions under Section 2255.

The majority's holding comes out of "nowhere" with "no support in the statute's text or history, nor can it be justified by our precedents," Justice Jackson wrote.

The decision also muddies the postconviction relief waters because it fails to "clearly establish ... what, exactly, does it mean for a prisoner to collaterally attack his conviction in the context of a compassionate-release motion," she argued.

"It is not hard to see how one man's collateral attack is another man's compelling bid for compassion," Justice Jackson wrote.

She added, "Perhaps even more troubling than the lack of support for today's holding is the uncertainty this case will create moving forward."

Justice Sonia Sotomayor argued in an opinion concurring only with the majority's judgment, which Justice Elena Kagan joined, that a "motion for compassionate release cannot justify a reduced sentence if it relies solely on facts a court already considered in imposing the initial sentence, rather than any changed circumstances that developed after sentencing."

The lower court judge should not have granted Fernandez relief, "given the absence of any postsentencing developments" in his case, and the justices should have ended their analysis there, Justice Sotomayor contended.

"Unfortunately, bad facts often make bad law, and so they did today," she wrote. "Correctly perceiving a problem with the district court's grant of relief, the majority responds with a rule that goes far beyond both what is needed to resolve this case and, worse, what the text and relevant precedents can bear."

Fernandez is represented by Benjamin Gruenstein of Gruenstein Law PLLC.

The government is represented by D. John Sauer and Eric Feigin of the U.S. Office of the Solicitor General.

The case is Fernandez v. U.S., case number 24-556, in the U.S. Supreme Court.

--Additional reporting by Matthew Santoni. Editing by Daniel King.

Update: This article has been updated with additional information and comments.

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