Georgia will prohibit the execution of people found "guilty but mentally retarded" when a newly signed bill prompted by a 1986 execution takes effect this summer.

The measure passed the 1988 General Assembly despite initial opposition to early drafts from prosecutors. Gov. Joe Frank Harris' signature last week puts it on the law books July 1.The law allows juries or judges if a jury trial is waived to return a new verdict of "guilty but mentally retarded" and stipulates that individuals so convicted could be sentenced to life but cannot be executed.

Georgia law previously allowed verdicts of not guilty by reason of insanity and guilty but mentally ill, but had no separate provision for the mentally retarded.

Before being allowed to enter a plea of guilty but mentally retarded, an individual would be required to undergo a psychological examination and satisfy the judge that there was a factual basis for him to enter the plea.

Atlanta lawyer Clive Stafford-Smith said Georgia may be the first state to take such a step.

The new law was prompted in part by widespread criticism of the execution of Jerome Bowden.

Bowden, whose attorneys contended he should not be executed because of mental retardation, was sentenced to death for a 1976 murder.

Despite the finding that Bowden's IQ was 65 100 is considered average the board concluded that Bowden knew right from wrong and voted to allow the execution to be carried out. He was executed June 24, 1986.