Michael Jackson's doctor was charged with involuntary manslaughter on Monday ahead of a long-awaited court hearing where he is expected to deny causing the pop icon's death.
A statement from the Los Angeles County District Attorney's Office -- which had already confirmed criminal charges would be issued against Conrad Murray -- set out the allegations against the 56-year-old physician.
Murray has been a focus of investigations for months, since the coroner's office ruled that Jackson's June 25, 2009 death was a homicide by drug overdose.
Murray was at Jackson's rented Los Angeles house at the time of his death and was the man who, according to police affidavits, admitted administering the powerful anesthetic propofol to the 50 year-old singer to help him sleep.
The coroner's report in August said Jackson's death was caused principally by propofol and the sedative lorazepam. A cocktail of other painkillers, sedatives and a stimulant were also found in his body.
The charge of involuntary manslaughter alleges Murray "did unlawfully, and without malice, kill Michael Joseph Jackson," said a statement from the Los Angeles District Attorney's office.
Murray is expected to make an initial appearance in court in Los Angeles later on Monday.
He could face up to four years in prison if convicted, the district attorney's office said.
The doctor has repeatedly insisted he did nothing wrong and has told investigators he was not the first doctor to give Jackson propofol, according to court records.
Murray, a cardiologist, was hired in May 2009 to care for Jackson while the entertainer prepared for a series of 50 comeback concerts in London aimed at reviving a career sidelined by his humiliating 2005 trial and acquittal on charges of molesting a 13 year-old boy.
The self-styled King of Pop died of sudden cardiac arrest after a late night rehearsal in Los Angeles for the planned concerts.
His death prompted a worldwide outpouring of grief for the singer, who started his career as a child and whose 1982 album "Thriller" remains the world's best-selling album.
Murray was an immediate focus of police investigations into Jackson's death. Authorities found bottles of propofol in Murray's doctor's bag and on the bedside table of Jackson's home, according to court records unsealed last year.
They also searched Murray's offices in Las Vegas and Houston, Texas.