We have never had the Death Penalty in this country.
A Death Penalty means that, if you commit such-and-such a crime that the law says you should get the DP for, you stop breathing pretty soon after you're found guilty and sentenced, after a reasonable interval in which you can try to show the verdict was wrong.
But in this country, people spend more than fifteen years, on average, between their sentence and their execution. More people who get the death penalty, die of old age than of execution, after the state generously supports them for the rest of their lives. Some deterrent.
A country that offers such slight deterrent to people who commit particularly horrible crimes like premeditated murder of its innocent citizens etc., is hardly "civilized".