11.   When states without the death penalty are included in the count, half the states no longer execute mentally retarded killers.

12.   A high court ruling is expected next fall in a North Carolina case that could outlaw executions of retarded killers.

13.   About two dozen states allow the execution of retarded killers, although some are considering laws prohibiting the practice.

14.   But in a landmark ruling, the justices also decided the Constitution allows the execution of mentally retarded killers.

15.   But the justices also decided the Constitution allows the execution of mentally retarded killers.

16.   Gov. Rick Perry knew the spotlight was on the Texas criminal justice system when he vetoed a bill to prohibit the state from executing mentally retarded killers.

17.   Gov. Jeb Bush signed into law Tuesday a bill banning the execution of mentally retarded killers.

18.   Some two dozen states allow the execution of retarded killers, though some are considering laws prohibiting the practice.

19.   The high court is expected to rule on a North Carolina case that could outlaw executions of retarded killers.

20.   The justices heard arguments in his case one day after announcing they will consider this fall whether the Constitution allows mentally retarded killers to be executed at all.