Police shut down two blocks of busy Ygnacio Valley Road near the Walnut Creek courthouse for a few hours to protect protesters, who were spilling into the street. But other than some shouting, there was not much trouble and no arrests have been reported.
The pro-Mehserle protestors say they were taking a stand to defend the former BART officer convicted of involuntary manslaughter in Grant's death.
"This thing is about a man who made an honest mistake and needs to pay his dues for what he did," demonstrator Brad Leach said.
"I don't believe that he woke up in the morning and just thought to himself and thought that he was going to kill a man; he's only human and he made a mistake," demonstrator Elicia Ramsey said.
Shouting back was an equal number of demonstrators who support Grant and claim Mehserle's involuntary manslaughter conviction was a miscarriage of justice.
"Just to be accountable for you actions, that's all we ask for people out here; you're in law enforcement, we look up to you and here you turn around, you kill us," demonstrator Eddie Matthews said.
"It doesn't matter what Mehserle thinks or did, it's a setup of racism where any black youth his is regarded as a problem," demonstrator Ellen Murray said.
The pro-Mehserle group includes at least one open carry gun advocate and many who say they have friends or family in law enforcement.
"I'm here to support law enforcement in general; Mehserle, I feel sorry for him, I think he's an experimental scapegoat for a situation that's been festering in law enforcement for a long time," demonstrator Kevin Thomas said.
And while a Contra Costa sheriff's SWAT team stood by, the sparring between the two groups never moved from verbal to physical.
The Walnut Creek BART station was closed for about 20 minutes.
The protest wrapped up about 5 p.m.