What are your views on capital punishment? In what circumstances (if any) can the death penalty be justified?

I believe that there are 2 different views on capital punishment. Some may argue that capital punishment is inhuman, and that people cannot and should not play god. However, the logic of governments is that, it will act as deterrence, as a warning to others. However, the effects are limited as those who often commit these serious crimes already now the consequences and are prepared to face them. Thus the question that arises is, is there any other way to punish the criminals? Prisons are built just for these circumstances. The purpose of prisons is to provide a place for the wrongdoers to reform. Therefore, instead of capital punishment, life imprisonment can be implemented. I believe that after the long years spent in prison, I believe that the person could change for the better. Furthermore, by keeping them in prison, it also prevents them from bringing more harm to society, which is what the death penalty aims to do in the first place. Another alternative would be caning. As everyone knows, caning is extremely painful and it leaves a scar for life. Thus, any those ex-criminals who want to commit crimes again will think twice about it as the caning experience will haunt them for life. All these coincide with the aim for deterring people from committing more crimes. If the same results can be achieved, why not use the methods that are less inhumane? Moreover, in the case of murder, by killing the criminal, it would still not bring the victim back to life, and if the judge sentences the criminal to death, would that not be the same as the murderer, taking lives away at their own will?
Therefore, I believe that the death penalty can only be justified in extreme circumstances. For example, mass murderers. By killing that many people, it shows that the person is beyond redemption, his sanity lost. People should all get a second chance, but they must show that they deserve it. Therefore, the death penalty should only be used for extreme cases, like mass murderers with disregard for human life, playing god themselves. However, it would be best if we do not resort to the death penalty at every available opportunity.