HARRISBURG — Lawmakers, advocates and law enforcement officials in Pennsylvania are debating whether it should be left up to judges or juries to decide when convicted criminals lack the mental capacity required for them to be legally executed.

The U.S. Supreme Court ruled eight years ago that criminals with mental retardation cannot be subject to capital punishment, but the ruling left it up to each state to determine how to handle such cases — and the commonwealth has yet to do so.

The issue came up again last week at a House Judiciary Committee hearing on a bill approved by the state Senate last summer. The measure, sponsored by Sen. Mary Jo White, R-21st, would give judges the power to make such a decision before a case goes to trial.

White argues that it makes no sense to go to the expense of a death penalty trial only to have a person deemed ineligible for the punishment — especially because capital trials are more expensive than other proceedings.

"Our criminal justice system is in danger. It's a budget-buster," White said.

County officials and many disability advocacy groups support the bill. Bill Burke, a board member of The Arc of Pennsylvania, said juries are not qualified to make the clinical diagnosis that someone is mentally disabled, and educating them would also take time and money.

"A person's mental retardation makes them vulnerable during the trial itself, which is why it is important to resolve the question of capital punishment before the trial commences," Burke said.

Law enforcement officials, however, argue that a jury should make the decision in such cases.

Dauphin County District Attorney Edward Marsico Jr. says juries already decide claims of insanity or self-defense, and the panels are better equipped to make the determination after hearing the facts of the case. Besides, he said, a possible death sentence gives attorneys more plea options.

"Passing this bill is an elitist response to a problem that really doesn't exist," Marsico said. "This bill tells our citizens they are not smart enough to decide this issue, even with instructions from a judge."

The state attorney general's office and the Fraternal Order of Police also oppose the plan, saying they fear that everyone facing a death penalty trial will try to convince the judge they are mentally impaired.

"This will be raised often," said Chris Carusone, chief deputy attorney general. "If there's any hint of a mental problem ... it will be raised."