Althought there is room for pipul in this halacha. A ben-Noach cannot kill a yid, under any circumstance. Rightfully killing a Yid, needs a besdin of musmachim. and jewish eidim.
Additionaly, they do have a decent argument, in his defence, from the legal/ethical standpoint.
Personaly I do not hold of the death penalty for this reason alone, that jews will die. But if we are talking about goyim, the world's judicial systems have full license and obligation to kill any goy for stealing even a Shveh Prutah. And a woman can be a judge (I don't remember about witness but I think so), and you only need 1 witness.
Yes, I do live by a double standard. Although by monetary issues, it's much harder to be nice to the "guilty" yid. True the jails will break any yid, in addtion to raping, and violently beating him..... but sadly that is the system. When we get into a car, we need to be aware that there is "implied concent" to take a breathalizer, and to C"V be jailed for the way we may drive. To a Yid, the US penal system is far more serious of a punishment, than for any normal inmate. If only there was a national unit/wing for every jewish inmate in the country.
Even if we had to fund the prison transfer, it would still be a wondersull solution.