It seems that the investigation into what exactly caused Michael Jackson's death isn't coming to an end anytime soon. The New York Times reported that a warrant was executed in Las Vegas this week which authorized the investigating officers to take a look at the letters exchanged between Jackson's doctor, Dr. Conrad Murray and his promoters, the Anschutz Entertainment Group.
According to Earl Paysinger, the current chief of the Los Angeles Police Department, they are not investigating the role of Anschutz Entertainment Group in this matter.
L.A.P.D isn't the only agency involved in this investigation. This high profile case is being investigated by various other departments simultaneously.