It’s a fundamental debate in democratic countries: how should society punish murderers?

It’s a fundamental debate in democratic countries: how should society punish murderers? Об terrorists? Or kidnappers?
In some countries capital punishment has been abolished. But it is still used in others. In the US, 39 states have the death penalty and 11 don’t. Different states use different methods of execution: the electric chair, gas chamber, injection of poison. In Russia, capital punishment still exists, but the parliament has started discussions about abolishing it.
At one time capital punishment was used for many crimes (offences). The Bible, for example, prescribed death for at least 30 crimes.

During the Middle Ages capital punishment was especially popular. Burning alive, hanging, beheading, stoning to death, drawing and quartering were quite common in those dark years.
Today, capital punishment is used (in those countries where it hasn’t been abolished) for only a few crimes, most commonly treason, murder, armed robbery and kidnapping. People disagree about whether capital punishment is moral or effective in preventing crime. Here are the most frequently used arguments for and against the death penalty:

FOR
• People who take human life deserve to lose their own lives.
• Capital punishment prevents crime because people are afraid of the consequences. The fear of death is more effective than the fear of prison.
• Capital punishment is a necessity because there are so many crimes, and prisons cost too much money.
• Many murderers are mentally ill. If we put them in prison, they can escape and commit another crime.

AGAINST
• Capital punishment lessens respect for human life. It is cruel and inhumane.
• There are other ways of punishing criminals. The fear of the penalty doesn’t help to prevent crime.
• We can’t always be sure that someone is guilty. People have been sentenced to death and later it was discovered that they were completely innocent.
• Capital punishment isn’t used fairly. The poor and defenceless are more likely to be executed than the rich and powerful.
And what do you think about it?

I have not yet decided on my opinion