Phillips is serving 31 years in a central California prison, and authorities said his violent streak flared anew when he allegedly killed his cellmate over the weekend.
Phillips, who played with the
Soward, a reputed gang member from the Inland Empire, was serving an 82-years-to-life sentence in the execution murder of Michael Fairley, a rival gang member known by the moniker "Trouble."
Long before Phillips landed in prison, he had gained a reputation with his anger and spontaneous bursts of aggression.
The Los Angeles native grew up in the foster system, where he was placed after it was suspected that he had been abused and neglected, according to The Times archives. When he landed at the University of Nebraska to play football, it appeared he had turned his life around.
Despite his football skills, things went wrong quickly. In college, Phillips was accused of bashing his girlfriend's head into a mailbox after he allegedly caught her in bed with the team's quarterback.
He pleaded no contest to charges of trespassing and misdemeanor assault in 1995.
The following year, Phillips was drafted by the Rams but ran into trouble when he was stopped for drunk driving on Pomona Freeway.
After being cut by the Rams in 1997, Phillips was signed by the Miami Dolphins, who cut him after he pleaded no contest to misdemeanor battery for allegedly hitting a woman who refused to dance with him at a Florida nightclub.
After playing in Europe, Phillips joined the 49ers, but financial and legal problems followed. He later pleaded no contest to felony charges of assault and making a terrorist threat.
He moved to San Diego where he was accused of punching and choking his girlfriend.
A week later, he showed up outside the Los Angeles Coliseum and ran over three teens he thought had stolen his belongings. He was ultimately convicted of domestic violence, false imprisonment and vehicle theft.
And if found guilty of killing his cellmate, the former athlete could face life in prison.
For now, prison officials said Phillips has been segregated from the rest of the prison population.