Death Penalty

I made a speech in Public Speaking. I chose the topic ' Should the death penalty be banned as a form of punishment'? as persuasive speech. In my opinion, I opposed this topic. It was because death penalty is the best way which reduces the perpetrators. My first evidence is that
the death penalty gives closure to the victim's families who have suffered so much. Second is
it creates another form of crime deterrent. Third is justice is better served. Fourth is our justice system shows more sympathy for criminals than it does victims. Fifth is prisoner parole or escapes can give criminals another chance to kill. Last proof is DNA testing and other methods of modern crime scene science can now effectively eliminate almost all uncertainty as to a person's guilt or innocence. For these reasons, I opposed the topic. Also, I have never changed the necessity of death penalty.