(this is the episode where Malcolm's mom got arrested)
1. If you have this episode taped, rewind and pause right before the exterior shot of Malcolm's house...just as he is about to reveal the tape of Lois's van to Reese.
2. Now press play. On the shot of the house, you should hear a high pitched laugh, which sounds identical to Reese.
3. However, a millisecond later, the next shot is on Malcolm and Reese, and Reese's face is totally straight. There is no way he could have had a straight face that quick after he laughed.