You didn't quite explicitly say this, but it sounds to me like you want to make sure every unjustly convicted person suffers as publicly and viscerally as possible in order to drum up the political will for change. (I can't think of any other principled reason to oppose a mechanism to free the innocent victims of an imperfect system.)
I suppose it's easy to feel that way when it's not you or one of your loved ones in that position. To them, it's not just a "fig leaf". It's getting their life back.
The rule of law and equality before it is a principal I believe in. Some politician being able to arbitrarily decide that the rule of law does not apply to a particular person is a violation of that principal.
Maybe one day you'll see why it matters.
> If you think someone needs a presidential pardon, just back up and think "which law is horrible and unjust and must be reformed." If not the law maybe the courts. Pardon at best is a fig leaf over a gaping wound.
Maybe you don't like to put it this bluntly, but it seems pretty clear that you were saying "pardoning is never justified, just reform the legal system instead." I saw no consideration in any of your statements for the possibility that some of these unfortunate souls could get some relief in the meantime while the long, hard, and uncertain work of reform is carried out. No, that would be "at best a fig leaf", meaning something covers up a dirty secret, alleviating shame and embarrassment.
If you feel I'm misrepresenting your original argument, I'm willing to listen to an alternative explanation of what you meant. But until one is offered, I stand by what I said. It was a reasonable interpretation of your words as you wrote them.
By the way, you keep describing this as the President "being able to arbitrarily decide that the rule of law does not apply to a particular person". This is an effective rhetorical technique because it conjures up images of corrupt witch hunts, political retribution, secret prisons, and other such nightmarish scenarios encountered in totalitarian distopias. You're leaving out the fact that the politician can only decide this in one direction - toward innocence. It can't be used to punish anybody. It can only be used to delight them. I consider this an example of the Noncentral Fallacy[0].
> Maybe one day you'll see why it matters.
Maybe, rather than putting on an air of dismissive superiority and suggesting that I'm just not wise and experienced enough to see the world the way it really is, you could provide an actual example of how it could matter to me in a negative way.
[0] http://lesswrong.com/lw/e95/the_noncentral_fallacy_the_worst...
https://en.wikipedia.org/wiki/Pardon_of_Richard_Nixon
That can affect you in a negative way.
Appeal courts rule on law. You see the difference?