I agree with Chicago in this instance, I think. His arm is clearly by his side, so you have to be sure that he is deliberately moving it towards the ball to give the penalty. The ball deflected a split second before hitting him so I don't think that's a reasonable assumption. They seemed to provide about a dozen ultra slow-motion replays but not once did they show it in normal speed to demonstrate how little time he had to move his arm. If that had been given against Villa this forum would be in revolt.