A unanimous Supreme Court ruled Tuesday that mentally ill prisoners do not have a right to put off their federal habeas corpus appeals while they try to regain mental competency.

Justice Clarence Thomas, writing for the court, dashed the hopes of criminal defense advocates that the justices would recognize a “right to competency” in habeas proceedings similar to the due process right to competency at trial.

The ruling came in Ryan v. Gonzales from Arizona and Tibbals v. Carter from Ohio, cases that were argued together last October 9. The Ninth and Sixth circuits, respectively, had granted stays in the appeals of convicted murderers Ernest Gonzales and Sean Carter.

Overturning both circuits, Thomas said relevant federal laws convey no right to such delays. He added that habeas proceedings are different from trials in ways that make it possible for lawyers to effectively represent mentally incompetent clients.

“Given the backwards-looking, record-based nature of most federal habeas proceedings, counsel can provide effective representation to a habeas petitioner regardless of the petitioner’s competence,” Thomas wrote. “Attorneys are quite capable of reviewing the state-court record, identifying legal errors, and marshaling relevant arguments, even without their clients’ assistance.”

Both appeals courts had found that a petitioner’s mental competency was important even in habeas proceedings. A brief filed in the cases by the American Bar Association also stated that a defendant’s statutory right to appointed counsel in habeas proceedings includes “both the right to knowing, rational communication and decision-making by the capital habeas petitioners and in appropriate circumstances, the right to an appropriate stay of proceedings when they are not competent to participate.”

Allowing routine stays for mental competency determinations, Thomas said, would thwart the goal of finality expressed in the federal Antiterrorism and Effective Death Penalty Act of 1996. “At some point, the state must be allowed to defend its judgment of conviction,” wrote Thomas. In a footnote, Thomas said Tuesday’s ruling did not affect the long-standing prohibition against actually executing a prisoner who is insane.

Thomas also said that “if a district court concludes that the petitioner’s [habeas] claim could substantially benefit from the petitioner’s assistance, the district court should take into account the likelihood that the petitioner will regain competence in the foreseeable future.”

Assistant Arizona federal defender Dale Baich, one of the lawyers for Gonzales, took solace from that concession by Thomas. “Even though the Court did not think an indefinite stay was appropriate, it did leave room for the district courts to temporarily stay habeas proceedings if the prisoner could assist the attorney, and it is shown that the prisoner could regain competence.”

Tony Mauro is the U.S. Supreme Court correspondent for The National Law Journal, a Legal affiliate based in New York.