THE VIRGINIA Supreme Court last week declined to order new DNA testing in the case of Roger Keith Coleman, whom the commonwealth executed in 1992 for a rape and murder that had occurred more than a decade earlier. Mr. Coleman's guilt, both before and after his execution, was a matter of great public controversy. An early form of DNA testing implicated him and he flunked a polygraph test on the day of his execution, but other evidence cast his conviction into doubt. More modern DNA testing methods likely would put the controversy to rest once and for all, and a group of newspapers, including this one, sought to do this testing. Yet the Virginia attorney general's office fiercely has resisted, and it now has won the battle. At least, that is, it has won the court battle. Gov. Mark Warner still has the authority to order the testing, and he should do so.

There is no good reason not to test the physical evidence that still exists. If Mr. Coleman was, in fact, guilty, the test could firm up one of the most shaky convictions to result in an execution in modern times. If he was innocent -- as he maintained publicly from the day of his arrest to his final words before his electrocution -- surely policymakers and the public ought to know, not least because it would imply that a rapist and murderer is still at large. Failing to test serves only to shield the state's death penalty and criminal justice apparatus from the possibility of a mistake coming to light. Everything that DNA testing has demonstrated about the fallibility of criminal trials ought to caution against such arrogance. Mr. Coleman's case has dragged on for more than 20 years. It should be unthinkable that it will end with the truth both knowable and willfully unlearned. Mr. Warner must not let this happen.