It may or may not be a deterrent to many of the death seeking murderers. But I for one rest much better when a horrible murderer is taken out of this world. Of course they have no life after they commit the act of murder. They will not have eternal life and they are best to be destroyed as soon as it can legally be done. This is why I personally felt that the Universe took a breath of fresh air after say Saddam Hussein was put to the gallows. This is a very righteous thing for the world to do in all of the cases of known murderers and by removing them from the world of the living they will never have any breath or association with life any time ever again. So the universe is healed and the rifts that are created begin to collapse. This is a very important thing. I am a very staunch liberal and I am very much for the Death Penalty at least in any case where it is unequivocal that the murder was committed by the said murderer.
I feel that this is the way that Our G-d wants us to conduct our business on earth. May the time of their final moment be soon and swift with the true legal process done appropriately.