“Does his pardon authority extend to local criminal cases?”
Sure, I think the president can pardon anybody. Not sure if he could pardon a person convicted of treason, but other than that, yes.
Most people that get presidential pardons are convicted on a state level, I don’t think there are all the many federal offenders.
I don’t know why presidents aren’t ever asked to issue pardons on death penalty cases. I remember the yammering about the woman executed in Tx, but I think that might have happened after Bush was elected but before he left office as Gov. of Texas, or maybe it was that he was being asked to use his influence on the next gov.
I don’t remember, maybe somebody will ‘splain it to us.
The President has no pardon or commutation power over state convicts such as Mumia.
He can’t pardon or commute illegal immigrants because their breach is civil, not criminal, but he could grant widespread relief from civil proceedings (including pre-removal detention) which a subsequent President might have difficulty reinstituting, practically or otherwise.
A raft of recess appointments to fill vacancies in the federal courts are certainly a possibility, but the damage potential is limited simply because few credible candidates would take so poisoned a seat. (Two or three strong candidates from states with two Democrat Senators is more likely, since they’d have a good chance at renomination by Romney in the typical distribution of judicial spoils.)
I believe that the president’s pardon power only extends to federal crimes.
You are incorrect. The President has no power to grant pardons to people convicted under State law.