Testifying as a defense witness for Mehserle in the fourth day of his preliminary hearing in Alameda County Superior Court, Domenici said Grant, a 22-year-old Hayward man who was unarmed, "didn't follow my command to sit" even though she ordered him to do so multiple times.
The purpose of the hearing is to determine if there's enough evidence to have Mehserle, 27, ordered to stand trial on murder charges.
Domenici said when she pushed back one of Grant's friends, Jackie Bryson, "Grant grabs my left arm and is holding on to me."
Domenici said Grant crouched down at one point but "never sat down on his bottom" and repeatedly said, "This is f---ed up."
Domenici, who has been a BART officer for more than four and a half years, said Grant apparently was referring to the situation on the Fruitvale station's platform about 2 a.m. on Jan. 1. She said she and other officers responded to reports that there was a fight on a BART train.
Domenici said another of Grant's friends, Michael Greer, "was very uncooperative with police" and refused to get off the train until her partner, Officer Tony Pirone, grabbed him, pulled him off the train and eventually pushed him onto the ground.
Mehserle's lawyer, Michael Rains, told Judge C. Don Clay, who's presiding over the hearing, that he is calling Domenici and other BART officers to the witness stand in an attempt to prove the defense's contention that, "This isn't murder because there's an absence of malice" on Mehserle's part.
Rains said Mehserle, who's free on $3 million bail, "was reacting to a struggling, resistant Mr. Grant."
The defense lawyer alleged that Grant "was not passive, did not have his hands behind his back obeying orders and was resisting until the shot was fired."
Last week Rains said that Mehserle meant to use his Taser on Grant and fired his gun by mistake.
Rains said he wanted Clay to allow officer Pirone to testify that Mehserle told him before the shooting incident that he planned to use his Taser on Grant, but the judge said such testimony would be inadmissible because it's hearsay.
The defense lawyer also said he wanted to be allowed to present evidence about Grant's felony convictions and short prison terms in order to demonstrate "Mr. Grant's character for aggression and violence," but Clay said such evidence is irrelevant and also would not be admitted.
However, Clay said he will allow Rains to present a witness who will play in court part of an enhanced, slow-motion video of the interaction between Grant and Pirone and Mehserle just before the shooting.
Referring to videos of the incident that were played in court by prosecutor David Stein last week, Clay said, "I don't need someone to tell me what I've seen."
But he said a slow-motion video "from the point when Grant is on the ground to the point where he (Mehserle) shoots Mr. Grant is relevant" to Mehserle's state of mind at the time of the shooting, which is a key issue in the case.
Domenici, Officer Jon Woffinden, who was Mehserle's partner that night, and Officer Emery Knudtson all testified today that they feared for their safety at the Fruitvale station because people on the platform and on the crowded train were unruly and noisy and were calling them names. Knudtson said he and other officers were on edge because there had been several reports that night of BART passengers carrying guns. He also said he tackled and detained a man who threw a cell phone at him.
Woffinden said that shortly before the Fruitvale station incident he and Mehserle had responded to an incident at the West Oakland station in which a man with a gun had jumped from the platform level to the ground.
Near the end of a lengthy cross-examination of Woffinden that began on Wednesday and concluded today, Stein suggested that in Woffinden's police report he had "exaggerated the facts to justify Officer Mehserle shooting Oscar Grant" and "to make it appear that you were in more danger than you really were."
But Woffinden said he didn't exaggerate anything and was truthful in his report and his testimony.
Stein also alleged that Knudtson left out many important details in the report that he wrote about the shooting incident.
Knudtson said he tried to include as much information as possible when he did his report the morning of Jan. 1 and left some things out only because he was exhausted after being up for more than 24 hours and on duty for more than 20 hours.
Domenici will continue her testimony when Mehserle's hearing resumes Wednesday morning.
Pirone apparently will follow her on the witness stand. Rains told Clay that he planned to call Pirone today if time allowed.