Washington ? The Supreme Court revealed deep divisions over the death penalty Monday as justices used unusually strong language regarding the constitutionality of executing people who killed when they were juveniles and allowing exceedingly long waits on death row.

The high court declined to hear two capital murder cases: one for a man given the death penalty for a killing committed when he was 17 and the other for a man who has spent nearly three decades waiting to die.

The court split along traditional lines, with the four more liberal justices saying the court should continue a re-examination of the death penalty begun last year when it banned executions of the mentally retarded. The four said it was “shameful” to execute juvenile killers.

“The practice of executing such offenders is a relic of the past and is inconsistent with evolving standards of decency in a civilized society,” wrote Justice John Paul Stevens, joined by Justices David Souter, Ruth Bader Ginsburg and Stephen Breyer.

No justice wrote separately Monday to defend the practice, but Justice Clarence Thomas expressed outrage at the thought of overturning death penalty convictions for longtime death row inmates.

The prisoner in this case, Thomas wrote, “could long ago have ended his ‘anxieties and uncertainties’ by submitting to what the people of Florida have deemed him to deserve: execution.”

The use of the death penalty has gotten increased attention in recent years as cases have emerged in which it was shown defendants received poor legal representation and genetic evidence proved the innocence of people sent to death row.

In Illinois, clemency hearings began this month for most of the inmates on that state’s death row. Executions are on hold there and in Maryland.

Only the United States and a few other countries allow execution of juvenile killers. States that allow the death penalty may impose it on killers who were 16 or 17 at the time of their crimes.

The juvenile case rejected by the court involved a Kentucky man sentenced to death for abducting, sodomizing and killing a gas station attendant when he was 17. Kevin Stanford, now 39, has been on death row since 1982. In 1989, the high court used Stanford’s case to uphold juvenile executions.

Stanford’s lawyers argued such executions violate not only the constitutional ban on cruel and unusual punishment but an international treaty signed by the United States. Like the retardation question, the issue of juvenile killers turns on the defendants’ capacity to understand their situation, and their level of culpability.