Grant's friend breaks down as his video plays

(06-12) 04:00 PDT Los Angeles - --

A teenager who was with Oscar Grant when former BART police Officer Johannes Mehserle shot Grant on a station platform wept uncontrollably on the witness stand Friday as he watched his own cell phone video of the incident.

Jamil Dewar, who is now 17, was composed at first as he described the events of Jan. 1, 2009, at BART's Fruitvale Station in Oakland to jurors in Mehserle's murder trial. But then Alameda County prosecutor David Stein started rolling Dewar's video.

It shows officers putting Grant, 22, on his chest to handcuff him after a fight on a train. Dewar, who was not among those being arrested, had stepped off the train and was moving around, trying to get a clear angle past officers.

His camera did not capture the actual shooting. But the bang of the gunshot is heard, as is Dewar's voice shouting, "He shot my cousin, man? He shot my cousin, blood?"

As the words rang out in the downtown Los Angeles courtroom, Dewar - who is not related to Grant but refers to him as a cousin - broke down, sobbing heavily with his head in his arms.

Stein asked Judge Robert Perry to stop the testimony for a lunch break, and Perry agreed. Then, as jurors filed out, Dewar's mother, Hope Dewar, ran up from the courtroom gallery to comfort him in the witness box.

Defense asks why

Dewar is not considered a make-or-break witness in the case, and his video doesn't show as much as some taken by other BART riders. But Mehserle's attorney was clearly concerned that his breakdown could sway jurors, because he brought it up during cross-examination in the afternoon.

Michael Rains asked Dewar why he didn't cry during a preliminary hearing in Oakland in May 2009. After all, Rains said, that courtroom had also been packed, his mother had been on hand, and the cell phone video had played.

"I haven't watched that video in a while," Dewar said.

Rains also went after Dewar for inconsistencies - testimony that differed from past statements he has made. And through Dewar, he gave jurors a look at the fight on the BART train that led to the New Year's Day incident.

A struggle with 'Diesel'

It was over very little, Dewar said. An ex-convict nicknamed "Diesel" became angry with Grant after Grant or one of his friends suggested the man's son was from the west side of Hayward. The two punched at and wrestled each other before the train pulled into Fruitvale and a BART officer arrived.

Dewar was the fourth prosecution witness of the day, after three others who captured video of the events on the train platform. Grant's mother, Wanda Johnson, who has seen her son shot to death on video over and over since the trial started Thursday, began dropping her head Friday and putting her hands over her ears at the moment Mehserle fired.

During opening statements Thursday, Stein said the footage showed that Mehserle, 28, had shot the unarmed Grant in the back intentionally and without justification.

Rains says Mehserle mistook his gun for his Taser and accidentally shot Grant, who the lawyer said had been resisting Mehserle's efforts to handcuff him.

Three of the witnesses who captured video - Dewar and fellow BART passengers Karina Vargas and Tommy Cross, neither of whom knew Grant - said under Stein's questioning that they had not seen Grant resist Mehserle or other officers.

"He had his hands behind his back. It didn't seem like he was squirming or fighting," Vargas said. She said she had heard Grant say, just before he was shot, "Don't Tase me, man."

Witness saw movement

The fourth witness, Daniel Liu, gave a somewhat different account. He said Grant's left arm had been "moving up and down" in the seconds before he was shot. He also said Grant and four friends who had been detained with him and ordered to sit against a wall were uncooperative at times, standing up to try to talk to officers.

Liu's tape shows former BART Officer Anthony Pirone - who first detained Grant and made the decision to arrest him - rushing toward Grant and aggressively forcing him to the ground a few minutes before the shooting.

Pirone has said he was reacting to Grant making a move toward his partner, Marysol Domenici, who like Pirone was recently fired from BART over the Grant episode.

Mehserle's demeanor

Vargas said that the atmosphere on the train platform was "chaos" and that some riders had thrown objects at officers. She said she feared a riot might break out "because of how angry they were."

Mehserle, though, "didn't look angry" before the shooting, she said. "He just looked like he was attempting to restrain him."

The witnesses said Mehserle looked stunned afterward, bringing his hands up to his head.

"I'd say dumbfounded would be the word," Vargas said. She said she hadn't heard Mehserle's reaction but added, "I did see him move his lips, and I'm assuming he said something like, 'Oh my God.' "

Cross, too, witnessed Mehserle's reaction, saying, "He looked up, and I looked at him, and he said either, 'Oh s-,' or, 'Oh my God.' "

Handcuffing Grant

The video taken by Cross shows something else: Mehserle appears to handcuff Grant after shooting him and taking a look at his wound.

Grant died later in the morning at an Oakland hospital. In the ensuing days, BART officials said it was standard procedure to handcuff a suspect who had been shot and might still be a threat.

All the footage jurors are seeing is powerful. On Vargas' video, BART riders can be heard responding emotionally to the realization that Grant had been shot.

"Oh my f- God," one person says. Others yell, "They just shot that guy," and, "Why did you shoot him?" and "I got you, motherf-," an apparent reference to another camera that was rolling.

One person shouts, "Get their badge numbers."

E-mail Demian Bulwa at dbulwa@sfchronicle.com.

This article appeared on page A - 1 of the San Francisco Chronicle