OAKLAND (CBS SF) — The Alameda County District Attorney on Monday announced that her office would not be filing new charges against former BART police officer Anthony Pirone following a lengthy investigation into his involvement with Oscar Grant’s death.

Alameda County District Attorney Nancy O’Malley had announced the reopening of the investigation into Pirone’s involvement with the death of Oscar Grant in late October of last year.

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Grant died early New Year’s Day 2009 after being shot in the back while laying on his stomach on the BART Fruitvale Station platform. Only former officer Johannes Mehserle has been charged in connection to his death;

Mehserle was tried and convicted of involuntary manslaughter in 2010. A judge sentenced Mehserle to two years in jail minus time served, and Mehserle was paroled after 11 months.

The release also noted that O’Malley and other representatives from her office had met with the Grant family on Monday to discuss the conclusions of the investigation.

Grant’s family has been calling for Pirone to be charged in connection with Grant’s death after a report from an internal affairs investigation was unsealed in 2019. The report claimed that Pirone’s actions were “aggressive and unreasonable” and noted that he used a racial epithet against Grant when he was being detained. Pirone also at one point knelt on Grant’s neck as the officers struggled with him on the BART platform.

While a statement released by O’Malley’s office Monday afternoon condemned “Anthony Pirone’s conduct in the strongest of terms,” the statement said the investigation “has concluded that he cannot be charged with murder or any other criminal offense.”

“Although Pirone’s conduct was aggressive, utterly unprofessional and disgraceful, it did not rise to the mental state required for murder,” O’Malley said in a video that was also released Monday afternoon.

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O’Malley’s office issued a 16-page report on Monday that detailed the investigation into Pirone’s action on the night Grant lost his life. In the report’s conclusion, it stated that the law “makes clear that Anthony Pirone can be guilty of murder only if he personally killed Mr. Grant, or if he aided and abetted the actual killer. In fact, Pirone neither killed nor aided and abetted Mr. Mehserle, who actually killed Mr. Grant.”

The conclusion also noted that the autopsy report on Grant gave no indication that the victim suffered from a head or neck injury that contributed to his death from Pirone placing a knee on Grant’s neck prior to the fatal shooting by Mehserle.

Attorneys for the Grant family had asked O’Malley to file felony murder charges against Pirone. With the passing of California Senate Bill 1437 in 2018, defendants can be charged with felony murder for aiding and abetting a killing.

Grant’s family on Monday maintained its position that Mehserle would never have been in a position to fire the fatal shot in the first place had it not been for Pirone.

“I’m not asking for different tham what our US constitution says or what our laws say,” said Grant’s mother Wanda Johnson. “I’m asking for him to be charged for his actions leading up to my son’s death. If it was myself who had done those things, I would definitely be in jail or prison.”

Grant’s family said their fight will continue. They want to sit down with their legal team and the DA, but have not yet set a date.

Earlier this month, the Grant family marked the 12th anniversary of Oscar Grant’s death by announcing the Alameda County District Attorney’s office knew the location of Pirone as they renewed their call for charges against him.

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The Oakland City Council and the BART Board are both scheduled to vote this week on resolutions urging District Attorney O’Malley to charge Pirone with felony murder.