Uh ... "most people" ?!?
I am not aware of that.
A murder should receive a corresponding harsh punishment, yes, but there is no such thing as "life in prison" anyway; there is no point to keep old people in prison, its just a pointless cruelty and an excessive waste of taxpayer money.
Because keeping people in a prison is a VERY expensive operation.
Here in europe we have penalties as low as seven years for murder and while thats maybe a bit short, even those countries dont have a problem with increased murder rates.
People who are able to murder other people - unless in self defense while fearing for my own life, I highly doubt I would be able to do such a thing and most of my fellow human beings are probably the same - dont function in such a way that they say "well if I only get X years I'll do it, but if I get death penalty I wont". As such, death penalty is completely ineffective and thus also a completely pointless cruelty, as it is forbidden by human rights.
There's class warfare, all right, but it's my class, the rich class, that's making war, and we're winning. - Warren Buffett