Can a sitting President of the United States be tried in a state court for state* crimes? I can see that as a practical matter it would be impossible for a state to compel the defendant to appear in court, let alone remand him or her to custody, but would there be any legal or constitutional provision for holding what’s a essentially a trial in absentia? Obviously in the event of a guilty verdict it would be up to Congress to impeach & remove the him or her from office; any custodial sentence would need to wait until s/he’s out of office one way or another.
*This part is important, as states have separate sovereignty from the federal government the President couldn’t try something like pardoning him or herself. Also separation of powers wouldn’t come into play.