A libertarian relying on governmental decisions to justify right v. wrong? How entertaining.
Where is this "right to life"? I've seen the Declaration of Independence speaks of "Life, Liberty, and the pusuit of Happiness", but those are not guaranteed rights. If they were, you'd be infringing on mine right now.
Are you suggesting there is no right to life? That we only have a right to live if the government so stipulates? That's preposterous.
Whether one believes the Creator endowed us with unalienable rights or whether one subscribes to Ayn Rand's philosophy, the right to life is clearly present. Only a disingenuous moron and you would suggest it doesn't exist. But I repeat myself.
If a man incarcerated in prison can and does lose his gauranteed rights, perhaps even his right to life, then what about US law makes you believe these rights are some how guaranteed to anyone?
My, but you're a dumb one! Capital punishment is meted out in response to an overt action on the part of the murderer (traitor, etc.). By committing the action and infringing on the rights of another person, the felon has forfeited their own rights.
If you haven't thought these issues through for yourself, you need to do so before coming on an Internet forum and discussing them. These are some of the most elementary principles I can think imagine, and it doesn't speak well of you that you're so clearly unprepared to discuss them.