Los Angeles ? Dr. Conrad Murray was in dire financial shape when he signed on as Michael Jackson’s personal physician earlier this year at $150,000 a month.

The Las Vegas cardiologist owed a total of at least $780,000 in judgments against him and his medical practice, outstanding mortgage payments on his house, delinquent student loans, child support and credit cards.

Court records chronicling Murray’s woes in Las Vegas, where authorities searched his home this week as part of a manslaughter investigation into Jackson’s death, might help explain why — beyond the chance to get close to a celebrity — Murray seized the chance to keep the pop star healthy through a series of concerts in London.

But more than that, the financial pressures on Murray could help prosecutors establish a motive if he ends up facing charges.

“Here he is, dealing with one of the most famous people in the world. There may have been a great deal of pressure to do what Michael Jackson wanted, give him the drugs he wanted, treat him the way Michael Jackson wanted to be treated, even if it wasn’t in keeping with medical protocol,” said Steve Cron, a criminal defense attorney and adjunct professor at Pepperdine University’s law school.

Authorities investigating Jackson’s death at his rented Los Angeles mansion believe Murray gave the star a fatal dose of the powerful anesthetic propofol to help him sleep, according to a law enforcement official who spoke on condition of anonymity because the investigation is still going on.

Propofol is commonly used for surgery and is not meant as a sleep agent or to be given in private homes. Because of its potency, only trained anesthesia professionals are supposed to administer it, and patients are supposed to be constantly monitored.

If prosecutors bring charges, Murray’s financial trouble “does potentially provide evidence of good motive for financial-based crimes, including prescribing when there is not a medical necessity,” said Rebecca Lonergan, a University of Southern California law professor and former federal prosecutor of health care fraud cases.