People's opinions about the death penalty

Although I don't agree with the death penalty, other people might think differently. So, I interviewed two people who are attending the university. Both of these people said that they strongly agreed with the death penalty. Their reasons were very similar. They said murderers might kill again and again if they don't get the death penalty. They also said they should realize that if they kill someone, they also will die. That's the only way to stop issues like murder.