Executions add to the glorification of violence that exists already too much in our society. The methods we use are ghastly. International law prohibits it. Civilized countries don't have it. Even China and the former Soviet states are abolishing it.
All humans have an inherent right to dignity and life.
The New Testament tells us that we should not play God, and that we should follow Jesus' example and show mercy. Also See Death Penalty Links , a fairly comprehensive source, the Death Penalty Information Center for online reports, or Capital Punishment 101 for background information.