Police have opened an investigation into the apparent drowning of Rodney King, the man who emerged as a reluctant "countercultural hero" after four LAPD officers brutally beat him in 1991.
King, 47, had been outside his house most of the night, his fiancée, Cynthia Kelly, told Rialto Police Capt. Randy De Anda after she reported finding his body at the bottom of the pool at his California home.
"[Kelly] was inside the residence, had been sleeping and Mr. King had been carrying conversations with her from the rear patio poolside," De Anda said. "She had heard him speaking to her. She got up to go outside to talk with him, at which time she found him at the bottom of the pool."
Click here to view a timeline of the events of Rodney King's life
It has been 20 years since King pleaded for blacks and whites to "get along," but recent cases like the killing of black Florida teen Trayvon Martin prove that the lessons of King's brutal beating at the hands of Los Angeles police have yet to be learned, the Rev. Jesse Jackson and other civil rights leaders said.
King emerged as a sort of reluctant, "countercultural hero" after he suffered the beating and a bystander's video camera captured the violence, Jackson told ABCNews.com.
That videotape, when shared with a Los Angeles TV station, sent shock waves around the world, catapulting police brutality and race relations in the United States to center stage and turning King into a symbol of the bitter conflict.
"It was his beating that made America focus on the presence of profiling and police misconduct," civil rights advocate the Rev. Al Sharpton said in a statement. "History will record that it was Rodney King's beating and his actions that made America deal with the excessive misconduct of law enforcement."
"Rodney King's case was a symbol of police abuse," Sharpton said at a march Sunday to protest the New York Police Department's stop-and-frisk policy. "I remember before the tape of Rodney King, we talk about police abuse people thought we were making it up."
Jackson compared King's case, in which his attackers were acquitted, with Martin's case today, in which killer George Zimmerman wasn't initially arrested for shooting Martin because of Florida's controversial "Stand Your Ground" law.
"We seem not to have learned the lesson of the ugliness of racial profiling and police brutality and all the pain it causes," he said.
The wake of the violent attacks on King and the subsequent L.A. riots in 1992 spurred the resignation of LAPD Chief Daryl Gates and an overhaul of the department, including years of federal oversight to monitor racial profiling and police brutality.
What was once a culture of low morale and a code of silence within a police force that had been scandalized even further by the O.J. Simpson murder trial was turned on its head under the leadership of former LAPD Chief William Bratton.
His emphasis on community-based policing and crackdowns on excessive use of force brought murders down to 297 in 2011, the lowest they've been in more than 40 years, according to KABC-TV in Los Angeles.
"The culture of the Los Angeles Police Department has been transformed," Erwin Chemerinsky, a professor and the founding dean of the School of Law at the University of California-Irvine, told KABC-TV.
Bratton has since gone on to advise the police forces of other major cities including London, where he now serves as a consultant to police after he city's spate of riots last year.
But 20 years after the 1992 acquittal of the LAPD officers ignited days of deadly riots in Los Angeles, Jackson said, the shooting of Trayvon Martin shows that race relations are still far from where they should be.
The NYPD, for example, has come under increasing criticism for its stop-and-frisk program, in which it detained more than 685,000 people in 2011, the majority of them young blacks and Hispanics, according to the New York Civil Liberties Union. That's up from about 97,300 stop-and-frisk incidents back in 2002.
Jackson said the persistent present-day bias is also reflected by the 8,000 blacks killed in the United States each year.
"It isn't just the police," he said. "Our concern now, of course, is too much racially-targeted violence.
"We had a redemptive moment with President Barack Obama's election," Jackson said.
But contrary to King's "resounding appeal for us to get along," he said, "it seems that we're not."
ABC News radio contributed to this report.