Any human institution / process is going to make mistakes.

Any human institution / process is going to be misused for personal, political, or venal purposes.

Capital punishment is irreversible, which means in the first case a mistake cannot be repaired at all; and it destroys information, which makes misuse in the second case harder to investigate.

People wrongly executed for murder are rarely random citizens. They're more likely neighbours, associates, colleagues, witnesses or family members of the real killer. Who get to sip Martinis as a potential source of evidence against them is buried by the State.

Personally, I'm not in favour of incarceration either. Its not just a waste of resources, its also mental torture and empowers sadists on both sides of the bars.

If we made residency/citizenship alienable, separately at local, state and national levels, that could be "seized" from criminals by a court and used / sold to compensate victims, with the criminal being given a decent interval to leave town before becoming an illegal alien/outlaw.

Some people will soon find themselves unable to get residency anywhere that isn't a "sanctuary city". Both they and the city will deserve it.