The death penalty is part of the same societal paradigm as war, as both are used by the state to impose control through violence, according to Sister Helen Prejean.

While 120 countries worldwide have suspended or abolished capital punishment, Japan and the United States stand alone among leading industrialized democracies in maintaining this system.

Prejean, 66, author of the highly acclaimed book "Dead Man Walking," was in Japan last week to campaign for a death penalty moratorium.