WASHINGTON - Prisoners have no constitutional right to DNA testing that might prove their innocence, the Supreme Court ruled on Thursday in a 5-to-4 decision.
The court divided along familiar ideological lines, with the majority emphasizing that 46 states already have laws that allow at least some prisoners to gain access to DNA evidence.
"To suddenly constitutionalize this area," Chief Justice John G. Roberts Jr. wrote for the majority, "would short-circuit what looks to be a prompt and considered legislative response."
The case before the court concerned Alaska, which has no DNA testing law. Prosecutors there have conceded that such testing could categorically establish the guilt or innocence of William G. Osborne, who was convicted in 1994 of kidnapping and sexually assaulting a prostitute in Anchorage.
In a dissent, Justice John Paul Stevens said the Constitution's due process clause required allowing Mr. Osborne to have access to DNA evidence in his case.
"For reasons the state has been unable or unwilling to articulate," Justice Stevens wrote, "it refuses to allow Osborne to test the evidence at his own expense and to thereby ascertain the truth once and for all."
Chief Justice Roberts acknowledged the "unparalleled ability" of DNA testing "both to exonerate the wrongly convicted and to identify the guilty." Such testing has played a role in 240 exonerations, according to the Innocence Project at Cardozo Law School, which represents Mr. Osborne. In 103 of those cases, the testing also identified the actual perpetrator.
Peter Neufeld, a director of the project, said Thursday's decision would have pernicious consequences.
"It's unquestionable that some people in some states who are factually innocent will not get DNA testing and will languish in prison," Mr. Neufeld said. "Some of them will die in prison."
Only four states - Alabama, Alaska, Massachusetts and Oklahoma - do not have laws in place specifically dealing with postconviction DNA testing, and Alabama recently enacted one limited to death row inmates that will become effective soon.
Many states that do allow postconviction testing impose conditions on who may seek it. Prosecutors often fight hard to deny access to DNA evidence even in states that nominally allow it, saying the prisoner in question had not met the statutory conditions.
Some laws, for instance, do not allow prisoners who have confessed to seek DNA evidence, though false confessions have been common among exonerated inmates. Other states allow testing only if it was unavailable at the time of trial.
Mr. Neufeld said the logic of Thursday's decision might allow constitutional challenges to some of those laws.
In the case from Alaska, District Attorney's Office v. Osborne, No. 08-6, Mr. Osborne sought to test biological evidence on a condom found at the crime scene, a snowbank near Anchorage International Airport. The victim was raped, beaten with an ax handle, shot in the head and left for dead. But the bullet only grazed her head, and she survived.
Rudimentary DNA testing on the condom in preparation for trial excluded two other suspects and included Mr. Osborne among those who might have committed the crime. The kind of testing used at the time, Chief Justice Roberts wrote, "generally cannot narrow the perpetrator down to less than 5 percent of the population."
Mr. Osborne's trial lawyer decided not to pursue a second kind of DNA testing that was more discriminating. The lawyer said she feared that the results might further incriminate her client. After his conviction, Mr. Osborne sued state officials in federal court seeking access to the DNA evidence for a third kind of yet-more-discriminating testing.
There was other significant evidence of Mr. Osborne's guilt, and he confessed to the Alaska Board of Parole, which released him after 14 years. He later said he had lied to the parole board in the hope of quicker release. Mr. Osborne has since been convicted of a home invasion.
Last year, the United States Court of Appeals for the Ninth Circuit, in San Francisco, ordered prosecutors in Alaska to turn over the DNA evidence, saying the most sophisticated form of testing had not been available at the time of the trial, that Mr. Osborne would bear its cost and that the results could provide a conclusive answer about his guilt or innocence.
Justice Samuel A. Alito Jr., in a part of his concurrence joined by Justices Anthony M. Kennedy and Clarence Thomas, was skeptical of all of the appeals court's rationales.
Allowing Mr. Osborne to forgo testing at trial and then request it from prison, Justice Alito wrote, "would allow prisoners to play games with the criminal justice system."
"After conviction," Justice Alito added, "with nothing to lose, the defendant could demand DNA testing in the hope that some happy accident - for example, degradation or contamination of the evidence - would provide the basis for seeking postconviction relief."
Justice Alito acknowledged that the testing Mr. Osborne now seeks was more advanced than the kind his lawyer failed to pursue.
"But his counsel did not decline" the less discriminating testing "because she thought it was not good enough," Justice Alito wrote. "She declined because she thought it was too good."
States would incur significant costs, Justice Alito added, were prisoners "given a never-before-recognized constitutional right to rummage through the state's genetic-evidence locker." And even the most sophisticated DNA testing, he said, "often fails to provide absolute proof of anything."
Although it has no DNA testing law, Alaska does have general procedures through which prisoners can try to gain access to evidence that might prove their innocence. The justices disagreed about how effective those procedures have been.
Chief Justice Roberts, whose majority opinion was joined by Justices Kennedy, Thomas, Alito and Antonin Scalia, wrote that he saw "nothing inadequate" about the procedures.
But Justice Stevens said no prisoner had ever obtained DNA evidence for testing in Alaska. He said Mr. Osborne "was rebuffed at every turn" by the state, creating "grave doubts about the adequacy of the procedural protections" in state law.
Justices Ruth Bader Ginsburg and Stephen G. Breyer joined all of Justice Stevens's opinion and Justice David H. Souter part of it.
Justice Souter issued a dissent saying that officials in Alaska had "demonstrated a combination of inattentiveness and intransigence" that add up to "procedural unfairness that violates the due process clause."
But Chief Justice Roberts concluded that the issue of when to allow DNA testing was best handled by the states.
"The question," he wrote, " is whether further change will primarily be made by legislative revision and judicial interpretation of the existing system, or whether the federal judiciary must leap ahead - revising (or even discarding) the system by creating a new constitutional right and taking over responsibility for refining it."