The arrest followed a 911 call from a woman, who was prevented by Barnes from finishing the call, according to police.
Police said they found signs of a fight in which both suffered injuries but concluded Barnes had been the primary aggressor.
On Thursday, Barnes' publicist, Laura Wright, identified the woman as Gloria Govan, an actress in VH1's "Basketball Wives."
Noting that Govan is her client too, Wright issued a statement from Govan, absolving Barnes.
"This is a situation that has been blown out of proportion," Govan said. "Any accusations of domestic violence are false. My fiancé, Matt Barnes, has never physically abused me or my family."
The Sacramento County district attorney will decide whether to file charges. On Thursday, spokesperson Shelly Orio said the office had yet to receive the police report.
Barnes' agent, Aaron Goodwin, couldn't be reached and a Lakers spokesman said the team would not comment.
Barnes did comment in a text message to Sacramento TV station KXTV, noting, "I was the victim but still got arrested."
And Barnes proclaimed his innocence on Twitter, noting:
"DON'T LET YOUR EARS WITNESS, WHAT YOUR EYES DIDN'T SEE!!!"
It has been a busy summer for Barnes, the UCLA alum who got the Lakers' attention last season in Orlando, engaging Kobe Bryant in a running argument and faking throwing the ball in his face on an in-bounds play with Bryant inches away.
Last month in a Bay Area Summer League game in San Francisco, Barnes reportedly slapped an opposing assistant coach.
According to an account by Rasheed Malek of WarriorsWorld.net, the assistant heckled Barnes, who was talking to a referee, telling him, "Stop your crying, you're in the NBA."
Malek said the two argued, but Barnes walked away before returning after the assistant continued "chirping... at which point Barnes gave [him] a slap on the face."
Malek called it "a love tap." Barnes and the assistant received technical fouls, but no other action was taken.
Govan was one of the five "Basketball Wives" in the show's first season, in a cast that included Shaquille O'Neal's ex-wife, Shaunie.
Barnes and Govan, who have twin sons, are billed as the show's happy couple.
However, for his part, Barnes said he found the show "disgusting."
Explained Govan to Essence.com: "He was surprised at how willing the women were to give information about other people and their own experiences. I'm not really sure that he's a fan of certain people on the show, but he's entitled to his opinions and the show is not focused on Matt."
Nor are anger issues unknown on the team. Ron Artest's baggage included a 2007 no-contest plea to misdemeanor domestic abuse — also in Sacramento — for which he was sentenced to 100 hours of community service.
Artest was a model of deportment last season, although he struggled to fit in — before becoming the star of the Game 7 victory over the Boston Celtics.
Similarly, the Lakers signed Barnes, at least in part for the emotion that has been his signature. Just not this much.