When the policeman strikes Jeff (Jeff's idea of what'll happen if he kisses Julia), his club folds up on Jeff's shoulder.
Susan passes Jeff and Julia in the hallway, both of them bent over with their foreheads on a pillar. As she continues on out of view, you can see Julia preparing and then raising her hand to stand up again as the shot switches.
As Jeff and Steve hide in Julia's toilet, Jeff flushes accidentally. But if you look at his elbow, it misses the flushing lever quite clearly.