The victory might give the Trojans a shot at a national title.
The Trojans (10-1), who have won four in a row since their only loss at Oregon State Oct. 28, came into the game third in the Bowl Championship Series standings, .08 points behind Michigan.
USC's lone remaining regular season game is next Saturday on the road against UCLA, and then it's up to the voters and the computers to calculate which team goes to Glendale, Ariz., to play Ohio State for the national title Jan. 8.
Booty completed 17-of-28 passes and was picked off twice, while Jarrett caught seven passes for 132 yards.
The Trojans had already clinched the Pac-10 title and secured at least a trip to the Rose Bowl on New Year's Day.
Brady Quinn connected on 22-of-45 passes for 274 yards with three TDs for the Fighting Irish (10-2), whose only other loss this season was at home, 47-21, to Michigan Sept. 16.