Law enforcement sources tell TMZ ... Winter passed away at his L.A. area home Friday of natural causes.

Winter was right there in front of the cameras in cases that include Michael Jackson, Whitney Houston, Brittany Murphy, Paul Walker, Tom Petty and Corey Haim.

Perhaps the most notable case involved Michael Jackson's death. Winter had immediate concerns when he saw a shocking number of injection points in Jackson's body. He was at UCLA Medical Center, where Jackson was taken, and immediately after he was pronounced dead he noticed Dr. Conrad Murray had left the facility. Winter said, "He fled."  Murray would have been the one to sign Jackson's death certificate, but Winter ended up doing it.

Winter later said Jackson had enough Propofol in him "to put down a rhinoceros or an elephant."

But Winter knew there was more to the story, and also set his sights on Dr. Arnold Klein, Jackson's dermatologist who fueled him almost daily with massive doses of Demerol. He tried to get Klein's medical records and eventually discovered Jackson had 19 aliases to score drugs, and Klein was a principal enabler.

Whitney Houston's death just before Clive Davis's 2012 pre-Grammy party was also a defining moment in his career. Winter had become such a staple on TV, he himself was very recognizable. After Whitney's body was discovered, her family gathered near her hotel room. Someone introduced a member of the family to Winter, and the woman said, "I know who Ed Winter is." The woman was Dionne Warwick.

On Winter's first day on the job, he was assigned to a notorious celebrity case -- the death of Lana Clarkson, at the hands of music icon Phil Spector, who was convicted of murdering her.

Paul Walker's horrific death was another high-profile case Winter managed. He went on TV to explain what happened in the car crash ... "He died instantly," Winter told reporters, despite reports the actor was screaming for help.