The seven-man, five-woman panel did request highlighters and blank forms to request evidence after starting deliberations around 8:30 a.m.
The jury must reach a unanimous verdict to either convict or acquit Dr. Conrad Murray of involuntary manslaughter in Jackson's June 2009 death.
Jackson died from a fatal dose of the anesthetic propofol; Murray has acknowledged giving Jackson propofol to help him sleep.
The group will deliberate during the court's regular hours and has not been sequestered. The trial is ending its sixth week.
During closing arguments, attorneys for the Houston-based cardiologist attacked prosecutors and their witnesses, saying they had over time developed stories and theories that placed the blame for Jackson's death squarely on Murray.
Prosecutors countered that Murray was an opportunistic and inept doctor who left Jackson's three children without a father. They said that Murray giving Jackson propofol as a sleep aid violated standards of care and amounted to a secret experiment in which the doctor kept no records.
Media were stationed outside the courthouse and in the courtroom where the jury's decision will eventually be read.
Attorneys handling the case will receive a two-hour notice when a verdict is reached. Murray waived the need for his presence if the panel asks any questions, but he must be present when a verdict is announced.
Jurors heard from 49 witnesses and have more than 300 pieces of evidence to consider. They were given lengthy instructions by the judge about how to deliberate.
If Murray is convicted, he faces a sentence ranging from probation to four years behind bars, and he would lose his medical license. The sentence will be decided by Superior Court Judge Michael Pastor after receiving input from attorneys for both sides and probation officials, if necessary.
A recent change in California law means that Murray, 58, might serve any possible incarceration in a county jail rather than a state prison. A prison term could be shortened by overcrowding.
If acquitted, Murray could still be pursued by medical licensing authorities in the states of California, Nevada and Texas.
To convict Murray, jurors will have to determine the cardiologist was substantially responsible for Jackson's death.
AP Special Correspondent Linda Deutsch contributed to this report.