The first-term Democrat said he came to the decision after months of review, meetings with victims’ families, prosecutors and law enforcement.
Inslee’s action is the latest of several state moves on the death penalty in recent years.
In Maryland, lawmakers last year did away with the death penalty, becoming the 18th state to do so and the sixth in six years. Colorado’s governor last year decided to indefinitely stay an execution, saying he had concerns about the fairness of the system and would be unlikely to allow the delayed case to move forward while he was in office. And Oregon’s governor in 2011 issued a moratorium similar to what is now in effect in Washington state.