That's an argument for improving our justice system, not eliminating a punishment altogether. Empirical evidence strongly suggests that such a reform is extrem

That's an argument for improving our justice system, not eliminating a punishment altogether. Empirical evidence strongly suggests that such a reform is extremely unlikely to happen -- and that in particular, we basically will never have a system win which the false conviction rate is not simply unacceptably high. So again, the argument is to at least design for "fault-tolerance", and not impose categorically irreversible sentences in the first place. 20 years in jail for an innocent person is no less horrible. If you were let out of jail after 20 years, I think you might disagree. But the bigger point is that the 20-year sentence can at least be appealed (and if overturned, substantially mitigated) if new evidence emerges that's relevant to your case -- as it very frequently does, in fact.