On Tuesday, Dr. Conrad Murray pleaded not guilty to involuntary manslaughter in the death of Michael Jackson at Los Angeles Superior Court. OK! NEWS: MICHAEL JACKSON MANSLAUGHTER CASE AGAINST DOC TO HAVE 30 WITNESSES Prosecutors will try to prove that Michael's death was caused by gross negligence, PopEater reports. Conrad could face up to four years in prison if convicted for involuntary manslaughter. His medical license has already been suspended, but he'll most likely never practice again ... Read More >>