A group of protesters frustrated by a Florida jury’s decision to acquit George Zimmerman brought mayhem to Los Angeles on Monday night. Demonstrations have continued there for three nights since the verdict was announced in the trial of Zimmerman, who claimed he was defending himself when he shot and killed Trayvon Martin, an unarmed teenager, last year.

The protesters in Los Angeles attacked passersby and broke windows, while in Oakland, a group briefly blocked a highway:

Thirteen people were arrested after multiple acts of vandalism and several assaults in Los Angeles’ Crenshaw District, Mayor Eric Garcetti and Police Chief Charlie Beck said at a news conference.

Garcetti and Beck didn’t elaborate on the assaults or any injuries, but at least one man could be seen in the street with a head injury.

More than 300 officers were called to the scene and were at first slow to directly engage protesters in an attempt to allow a peaceful end to the demonstration, Beck said. But the chief said police would take a much stricter posture in the coming nights.

“This will not be allowed to continue,” Beck said.

Several hundred mostly peaceful protesters gathered Monday night at Leimert Park southwest of downtown LA, many of them chanting, praying and singing.

But a smaller group of between 100 and 150 people splintered off and began blocking traffic on nearby Crenshaw Boulevard, some of them jumping on cars and breaking windows at liquor stores and fast food outlets. . .

TV news helicopters showed some people kicking and punching others along the street, including two people sitting on a bus bench.

Police declared the gathering an unlawful assembly about three hours after it began, and most of the crowd left the street.

Garcetti, who returned early from an East Coast trip because of the demonstrations, praised the “overwhelming majority” who protested peacefully.

“We are a better city than what we have seen tonight in the hands of a few people,” the mayor said.

In Oakland, dozens of demonstrators briefly blocked all lanes of Interstate 880 at the tail end of rush hour, stopping traffic in both directions for several minutes before lanes were cleared by authorities. Several protesters laid their bicycles on the ground in front of stopped cars.

“You’ve got to go. You will go to jail,” one police officer shouted at demonstrators who were blocking traffic, the Oakland Tribune reported. However, police decided not to make arrests as the marchers, chanting “Justice for Trayvon Martin,” were directed back to surface streets.

Associated Press

Some protesting George Zimmerman's acquittal in the shooting death of Trayvon Martin were arrested after confronting police in Los Angeles. (Associated Press)

Martin was black, and many believe the case reveals racism inherent in the criminal justice system. A black woman was convicted in a similar case in Florida recently, although she claimed she was defending herself:

Marissa Alexander, a 32-year-old mother of three, fired what she described as a warning shot in the direction of her husband — against whom she had a protective order — and two stepsons. No one was injured, but she was convicted of attempted murder and sentenced to 20 years.

In the wake of the Zimmerman trial and the national debate on race and justice that it prompted, Alexander’s case — from 2010 — has drawn renewed attention, including an online petition seeking a pardon from Florida Gov. Rick Scott (R) that has generated more than 36,000 signatures.

Supporters say Alexander, who is African American, was a victim of ingrained racism in Florida’s courts. Some say that those same alleged prejudices allowed Zimmerman, who has a white father and a Peruvian mother, to walk free after killing Martin, who was black. . .

Kevin Cobbin, Alexander’s attorney, said his client was justified in firing her gun because Gray “had put his hands on her and there was a fight in the bathroom.”

“The judge decided not to make the call to grant ‘stand your ground,’ ” Cobbin said. “If it had been a white female, I believe she would have.”

Rep. Corrine Brown (D-Fla.), whose district includes parts of Jacksonville, last year described Alexander’s case as evidence of “institutional racism.”

But [state attorney Angela] Corey said there are other, less widely shared details that paint a different picture.

She said Gray’s sons were pulling on their shoes to leave the house when Alexander raised her weapon to fire — in other words, they and their father were about to leave.

While online accounts sympathetic to Alexander say she fired shots into the ceiling, the single bullet she fired actually hit the wall, not far from Gray and the boys, then ricocheted into the ceiling, Corey said.

Billy Kenber

One juror in Zimmerman’s case talked about the jury’s thinking on Monday:

The woman, known as Juror B37, told CNN’s Anderson Cooper on Monday that when the jury began deliberations Friday, they took an initial vote. Three jurors— including B37 — were in favor of acquittal, two supported manslaughter and one backed second-degree murder. She said the jury started going through all the evidence, listening to tapes multiple times.

“That’s why it took us so long,” said B37, who said she planned to write a book about the trial but later had a change of heart.

When they started looking at the law, the person who initially wanted second-degree murder changed her vote to manslaughter, the juror said. Then they asked for clarification from the judge and went over it again and again. B37 said some jurors wanted to find Zimmerman guilty of something, but there was just no place to go based on the law.

B37 said jurors cried when they gave their final vote to the bailiff. . .

Juror B37, the only juror to speak publicly about the case so far, said Monday that the actions of Zimmerman and Martin both led to the teenager’s fatal shooting, but that Zimmerman didn’t actually break the law.

While Zimmerman made some poor decisions leading up to the shooting, including leaving his car when police told him not to, Martin wasn’t innocent either, the juror said.

“I think both were responsible for the situation they had gotten themselves into,” said the juror. “I think they both could have walked away.”

Associated Press

Although Zimmerman has been acquitted, Martin’s family might still bring a civil lawsuit against him. The Justice Department could also prosecute him on federal civil rights charges, although that seems less likely:

Current and former Justice Department officials said Monday that bringing civil rights charges against George Zimmerman in the shooting death of Trayvon Martin, an unarmed black 17-year-old in Florida, would be extremely difficult and may not be possible.

Attorney General Eric H. Holder Jr. vowed to continue a federal investigation of the matter, but other officials said in interviews that the government may not be able to charge Zimmerman with a federal hate crime because it’s not clear that he killed Martin because of his race.

The weakness of the evidence compounds the political problems facing President Obama and Holder, who are under mounting pressure from many liberal and African American groups to bring a federal case against Zimmerman. . .

Justice Department lawyers are reviewing an investigation of Martin’s shooting begun last year in conjunction with the FBI and state prosecutors in Florida, officials said. Prosecutors are combing through that evidence, as well as testimony from Zimmerman’s state trial, to determine whether to file civil rights charges.

“The Department of Justice couldn’t bring this case unless they believe they could prove to a jury beyond a reasonable doubt that George Zimmerman killed Trayvon Martin because of his race,” said Rachel Harmon, a law professor at the University of Virginia and a former prosecutor in the Justice Department’s civil rights division.

“It’s not enough to show that Zimmerman followed Trayvon Martin because of his race,” Harmon added. “They would have to show that he attacked Martin for that reason. . . . Proving that motive is why it’s hard to bring hate crime charges in general and why it is likely to be hard to bring them in this case.”

Philip Rucker and Sari Horwitz

Joel Achenbach writes that the controversy is symptomatic of deeper cultural divisions nationally:

Increasingly I worry that we’re becoming two Americas on every issue, from climate change to energy policy to fiscal policy to the truth about evolution or anything else that’s remotely political, scientific or cultural, and that this division is being exacerbated by the news media, partisans, charlatans and assorted bloviators in the Angersphere who never met a topic they couldn’t demagogue. (Another dangerous trend: Run-on sentences.)

Look at the reaction to the Zimmerman case, both in published commentary and just in the comments posted on news articles. There are two realities dueling here, both based around the belief that this was an outrageous miscarriage of justice, but with opposite conclusions about who the victim was.

Of course my version of reality is the correct one. That goes without saying.

To me this was a clear case of racial profiling, with a wannabe cop packing a gun deciding that there was something innately suspicious about a black kid walking through his neighborhood. Trayvon Martin was on his way home from getting a snack. Zimmerman initiated the encounter, which escalated into tragedy. The prosecution (by all accounts) put on a weak case. I didn’t watch the testimony so I won’t second-guess the verdict. It had many precedents in Florida going back to the McDuffie case, and Alvarez. Note that the jury wasn’t asked to decide if Zimmerman behaved correctly, or morally, or whether it makes any sense for crime-watch volunteers to be packing guns, or whether Zimmerman’s failure to stay in his car rather than provoke an encounter was a catastrophic mistake — only whether the shooting was a crime under Florida law. . .

The dueling realities are the product of a society that increasingly succumbs to demagoguery and profit-driven divisiveness. There is an emerging field called cultural cognition. It studies how we think, and why, and how these opinions are shaped by our cultural affiliations. There are topics like climate change that get sucked into the vortex of ideology, and then people decide what’s true and not true based on their identity with a cultural group rather than a cold-eyed analysis of the facts.

Joel Achenbach

For past coverage of the verdict, continue reading here.