Los Angeles ( CNN ) -- Jurors in the involuntary manslaughter trial of Michael Jackson 's doctor will hear closing arguments from the prosecution and defense Thursday , with deliberations on Dr. Conrad Murray 's fate expected to begin late Thursday or Friday . It follows 22 days of testimony from several of Murray 's girlfriends and patients , Jackson employees , paramedics and emergency room doctors , investigators and medical experts . Jackson 's mother will sit on one side of the courtroom , while Murray 's mother is likely to be seated on the other end Thursday as the seven men and five women on the jury listen to each side sum up their case . Jackson was preparing for a series of 50 shows in London , part of a career comeback , when he died on June 25 , 2009 . Murray told detectives in an interview two days after Jackson 's death that he had used the surgical anesthetic propofol to help Jackson sleep nearly every night for the previous two months , with the exception of his last three nights . He was using the sedatives lorazepam and Midazolam in an effort to wean Jackson off of propofol the morning he died , Murray said . When those drugs were n't working after almost 10 hours of trying , he gave him a single injection of propofol , which did put Jackson to sleep , he said . Jackson 's death was caused by `` acute propofol intoxication '' in combination with two sedatives , the Los Angeles County coroner ruled . The prosecution contends Dr. Murray 's use of propofol to treat Jackson 's insomnia was so reckless it was criminally negligent and caused the singer 's death . Murray failed to perform the legal obligation as a doctor because his treatment egregiously and extremely deviated from the required standard of medical care , the prosecution alleges . The defense contends that Jackson , not Murray , administered the fatal doses of propofol and sedatives the coroner ruled killed the pop icon . He was so desperate for sleep , and afraid his comeback concerts would be canceled without it , that he injected himself while Murray was not watching , the defense argues . Prosecutors say it makes no difference how the propofol got into Jackson 's blood since it was Murray who brought the drugs into the bedroom and left him alone long enough to die . Los Angeles County Superior Court Judge Michael Pastor will start Thursday 's court session by instructing the jury on the law guiding the decisions they must make . The jury must unanimously agree on one of two theories in order to convict Murray on the single count of involuntary manslaughter . The first theory is that Murray 's administration of propofol to Jackson was criminally negligent and it caused Jackson 's death . Although it was legal , as a licensed doctor , for Murray to administer propofol to Jackson , they could find he was reckless in the way he did it , which created a high risk of death . Criminal negligence requires more than just ordinary carelessness , inattention , or mistakes in judgment , the judge will tell jurors . A reasonable person would have to have known that the action would create such a risk of death . Prosecutors have laid out a list of acts they allege were negligent , including not having other medical staff present when propofol was used , a lack of monitoring equipment , ineffective resuscitative care when Jackson stopped breathing and a delay in calling for an ambulance . Using propofol , which is intended to sedate surgical patients , for sleep was another egregious deviation , they argue . The second theory that jurors could accept is that Murray , who assumed a legal obligation to care for Jackson when he became his physician , failed to perform this legal duty by deviating from standards of care required of a doctor , including , when he left him alone and unmonitored after administering propofol . The judge asked lawyers to finish their closing arguments by the end of Thursday , so the jury could begin deliberations . Murray , if convicted , faces up to four years in prison and the loss of his medical license .
Jurors have two theories of guilt to consider for Dr. Conrad Murray . One is that he was a victim who killed himself in an attempt to cover up his drug addiction. The defense contends Jackson gave himself the fatal overdose .