Next possibility:

"We shouldn't kill people because of the possibility of error – how do we know we're not executing an innocent man? We can't undo it afterwards."

I used to buy this objection, but strangely enough, law school has persuaded me otherwise. Because error is a deliberate policy choice of the criminal justice system.

Criminal trials require a finding of guilt "beyond a reasonable doubt". It does not require evidence "to an absolute certainty". That's a pretty big gap, when you think about it. So it's flatly incorrect to say that accuracy is the primary goal of criminal justice. It's high up on the list, but not at the top.

We'd like to think we're not punishing innocent people, but statistically, there's going to be a lot of cases that fall into the gap between "reasonable doubt" and absolute certainty. Not maybe. Definitely. When the criminal justice system is working at maximum accuracy, innocent people will still be put in jail.

Could we improve accuracy? Sure, by increasing the evidentiary threshold for conviction. If we required something closer to "certainty" we'd avoid false positives (erroneous convictions). But we'd also increase the number of false negatives (erroneous exonerations). So while we'd know innocent people weren't going to jail, we'd also know a lot of guilty people were going free.

This is apparently not acceptable, so we engage in a utilitarian calculus about how many false positives we're willing to tolerate in return for an acceptable conviction rate. Hence, reasonable doubt.

Maybe you're willing to accept error when it comes to imprisonment, but not for execution. That's fair. Certainly we could increase the evidentiary standard for capital punishment. Even the Constitution requires "the Testimony of two Witnesses ... [or a] Confession in open Court" for a treason conviction, which is typically punishable by death.

I have no idea of certain states use a higher burden of proof for capital cases. Ultimately the problem with this position is that it suggests accuracy is the issue, and that maybe the death penalty would be OK if you had enough evidence. So this is a flawed objection.

21 Jan 06