Washington ? In blocking the execution of a Texas killer, the Supreme Court revealed interest in a new area of capital punishment: the mentally ill.

The court ruled earlier this year that mentally retarded defendants cannot be executed, and last month the justices displayed division over whether people who were minors when they committed capital crimes should be put to death.

Those two issues have overshadowed questions about whether some of America’s 3,700 death row inmates are too mentally ill to be executed.

“It hasn’t gotten as much attention, but I think it deserves attention,” Atlanta death row lawyer Stephen Bright said Thursday.

The Supreme Court issued a last-minute stay Wednesday night that stopped the execution of 42-year-old James Colburn, who suffers from paranoid schizophrenia, hears voices and repeatedly has tried to kill himself.

The Supreme Court ruled in 1986 that executing an insane person would violate the Eighth Amendment ban on cruel and unusual punishment.

However, death penalty opponents like Bright argue that few mentally ill people qualify under the court’s definition: they must be incapable of understanding why they are being put to death or what they did wrong.