Santaquin Police Chief Dennis Howard said an autopsy found Coleman died of natural causes after an accidental fall. The finding matches the evidence police found at Coleman's Santaquin home on May 26, Howard told The Associated Press.
The state medical examiner's conclusions bring the police investigation into the death to a close, Howard said.
The 42-year-old actor died at a Provo hospital two days after his fall. He was taken off life support after suffering a brain hemorrhage.
An e-mail message sent to a spokeswoman for Coleman's former wife, Shannon Price, who made the decision to remove him from life support, was not immediately returned late Wednesday.
Coleman became a star after "Diff'rent Strokes" debuted in 1978. For eight seasons, Coleman played Arnold Jackson, the younger one of a pair of African-American brothers adopted by a wealthy white man. The tiny 10-year-old's "Whachu talkin' 'bout?" became a popular catch phrase from the show.
Coleman's adult life was plagued with heath and legal problems.
He moved to Utah in fall 2005, and according to a tally in early 2010, officers had been called to assist or intervene with Coleman more than 20 times. In one instance, Coleman called police for help after he claimed he had taken dozens of pain killers and "wanted to die."
Some of the disputes involved Price, whom he met on the set of the 2006 "Church Ball" and married in 2007. The couple divorced a year later but continued to live together and present themselves as married in public.
Price has petitioned the Utah courts to recognize her common law relationship with Coleman from the date of their divorce through his May 28 death. She is seeking the recognition as part of an ongoing legal battle over Coleman's estate, which includes the house in Santaquin, about 65 miles south of Salt Lake City.
Coleman, who was cremated weeks after his death, left multiple wills, although a note handwritten by Coleman days after his 2007 marriage names Price his sole heir.
Coleman's ex-girlfriend Anna Gray contends a 2005 document awards her the estate.