Bob Egelko has this story in the SF Chron. "Crime is seldom a prominent issue in presidential primaries, largely because the front-runners in each party typically take similar positions. But the subject can explode on Democrats in a November election."

Egelko notes that the positions of Clinton and Obama on the death penalty were once sharply different but have since converged. I'm inclined to think this is the result of changing political calculations rather than actual change in personal beliefs. As Obama moved from one state senate district to a statewide race for U.S. Senate, his previous forthright opposition wasn't going to fly. Clinton may not see the need to maintain emphatic support as the issue moves down on people's priority lists and as she moves to a race where other issues have relatively higher prominence.

The biggest impact a president has on state criminal cases is in who he or she appoints to the federal courts, and there "the difference between the parties is huge," the story quotes yours truly at the end.