WRONG
Any and all crimes.
The Watergate break in was not a federal crime, neither was covering up a burglary.
YOU MIGHT TRY LOOKING before you repost incorrectly
On September 8, 1974, president of the United States Gerald Ford issued Proclamation 4311, which gave Richard Nixon a full and unconditional pardon for any crimes he might have committed against the United States while president
TRY THE CONSTITUTION FOR THE WORDING does not include impeachmebnt
It occurred in D.C. -- a federal reservation.
Thus, federal jurisdiction...and federal crimes.
The President's pardoning authority IS limited to federal crimes.