Would you say the same for a Jew?
In theory, sure, but why would they release him?
Parole. Note that the Rambam disagrees. Roztach 2:4 & 2:5.
? ???? ??? ??????? ?????? ??? ????? ???????? ???? ??? ???–?? ??? ??? ????? ?????? ???? ?????? ????? ?????, ????? ????. ??? ?? ??? ??? ??? ????? ???? ?????? ???–?? ????? ???? ????? ???, ??? ?? ??? ???? ??? ?? ?????.
? ??? ??? ???? ????, ??? ????? ???? ????? ???? ????–??? ??? ??? ?????? ??? ???? ?????? ??? ??? ?????? ?????, ?????? ???? ????? ?????? ???? ????, ?????? ??? ???? ???: ??? ?????? ?????? ?? ??? ??????, ??? ???? ??? ???? ????? ??????? ???, ????? ????? ???? ????? ????? ???? ???? ?????, ??????.
So an individual has no right to mete out his own punishment in any of these scenarios.
It means he’s still a threat, so it does mean that.
If someone (Jewish) is hypothetically a threat to kill someone (unknown and not specific) 20 (or more, or less) years down the road, even 50/50, you would execute them today?