I might subscribe to that view if it actually solved something. I believe we had a burgeoning "bring back hanging" movement here in the UK as well, but something got in the way of a full blown return to what some would describe as "natural justice"
It was called "unsafe convictions"
Keeping people in a zoo doesn't work either in fact, some would argue that it's even more barbaric.
As ever, the answer would appear to be a compromise. "Atoning" for the crime would to me, at least, meaning setting the records straight, or balancing the Book of Life.
A killer would be in Public Service for the rest of their natural lives.
It would have to be worked out but an atonement - a public service in the public eye for life - that might have some positive impact.
OK Vigilantes! You may have the floor back! Off with their heads!