Nine medical staff are set to give evidence that Michael Jackson was mentally unstable at the time of his death.

Lawyers acting for Dr. Conrad Murray ' who is due to stand trial for the involuntary manslaughter of the music legend following his passing from acute Propofol intoxication in June 2009 ' have a list of 103 potential witnesses, including doctors and nurses, in hope of strengthening his claim that he did not administer the lethal dose of the anaesthetic that killed the iconic singer by exposing Michael's erratic behaviour and demanding personality.

Among those who could be called as witnesses are Dr. Arnold Klein ' a dermatologist who Murray's lawyers previously blamed for getting Michael addicted to painkillers ' and Cherilyn Lee, a nurse who claims the 'Thriller' hitmaker asked her for Propofol in the weeks leading up to his death, but she refused to supply the powerful anaesthetic.

A source told RadarOnline.com: "Cherilyn is prepared to testify at the trial and tell the truth. Cherilyn has never spoken with anyone from the District Attorney's office. She was interviewed in the weeks after Jackson's death by the coroner and the LAPD. Cherilyn hasn't heard from those agencies since that time."

Dr. Neil Ratner, who toured with the singer in 1996 and 1997 is also on the witness list following previous claims that he would keep medical equipment which would monitor his client's vital signs as he was "under."

Ratner was allegedly hired to combat the singer's sleeping problems by "taking him down" and "bringing him back up", a CNN report has previously claimed.

It is expected that Murray's lawyers will quiz Dr. Ratner about the specific details of his medical treatment for the star, as he has previously refused to disclose more than the fact Michael had a sleep disorder.

Dr. David Adams, a Las Vegas anaesthesiologist who gave the singer Propofol at least four times for medical reasons, will also be asked to testify.

According to a source, the defence feels "Dr. Adams is clearly relevant."

Jury selection for the trial begins on September 8, with opening arguments scheduled to begin on September 26, with the case potentially lasting until November.

Dr. Murray could be jailed for up to four years if convicted of involuntary manslaughter.