http://www.tmz.com/2011/09/28/conrad-murray-trial-manslaughter-michael-jackson-ucla-medical-center-waiting-room-hospital-surveillance-footage/

DR. CONRAD MURRAY [VIDEO]
Pacing Frantically in Hospital
... After MJ Dies

Prosecutors claim the tape shows Murray leaving the hospital around 4:36PM that day -- two hours after MJ was pronounced dead.

The defense refuted the claim -- and showed additional footage -- which appears to show Murray in the hospital around 5PM (notice the timestamp).