A doctor who treated Michael Jackson during a 1993 concert tour which had to be cancelled when the singer entered rehab has testified about the signs that led him to conclude the singer had a problem with prescription pain medications at the time.
In videotaped testimony, Dr Stuart Finkelstein said he was later asked by concert promoter AEG Live to act as Jackson's personal physician during the ill-fated "This Is It" tour in 2009 but wanted to know if Jackson was "clean".
AEG executive Paul Gongaware said he didn't believe Jackson had any prescription drug issues, Dr Finkelstein testified.
His testimony was recorded during a February deposition that was played for jurors in Los Angeles hearing a negligence lawsuit by Jackson's mother against AEG Live LLC. Katherine Jackson claims AEG failed to properly investigate another doctor who later gave her son an overdose of the anaesthetic propofol and that the company ignored warning signs about her son's health.
Dr Finkelstein said he first suspected Jackson had a dependence on pain medications in 1993 while working on the "Dangerous" tour. He recounted spending 24 hours in the singer's hotel suite and administering morphine intravenously to deal with Jackson's pain.
He said he gave Jackson morphine during their first meeting because the singer's buttocks were scarred from previous unspecified treatments and he was concerned about giving an injection of the painkiller Demerol.
He said he also noticed that Jackson appeared to have a high tolerance for morphine and had on a patch that administered another opiate drug.
Jackson died after Dr Conrad Murray administered an overdose of propofol on June 25, 2009. Murray, who agreed to work on the "This Is It" shows for 150,000 dollars (£100,000) a month, provided Jackson with propofol as a sleep aid.
AEG Live denies it hired Murray and says it bears no responsibility for Jackson's death.
Murray is in prison after being sentenced to four years behind bars for involuntary manslaughter.