Death Penalty in the USA

There are many arguments for and against the death penalty. Identify and Discuss the single most convincing argument that, in your opinion, is the strongest one IN FAVOR of the having/using the death penalty in the U.S. Then, take the opposite view and identify and discuss the single most convincing argument that, in your opinion, is the strongest one AGAINST having/using the death penalty in the U.S.

You must choose one argument for each side, and make sure you tell me why you think the one you selected is the strongest/most convincing using evidence from relevant sources .