OAKLAND (CBS SF/AP) – Newly released documents are providing more insight into the deadly shooting of Oscar Grant on a BART platform more than a decade ago.

On New Year’s Day in 2009 BART Police Officer Johanes Mehserle shot the 22-year-old in the back, later saying he thought he grabbed his taser. Mehserle served 2 years in prison for involuntary manslaughter.

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Ten years after her son’s death, Wanda Johnson, Grant’s mother – says this new report reveals what she has known for a decade – that her son didn’t have to be murdered.

“They knew from the beginning, but yet still tried to cover it up,” Johnson said.

According to the crime report, investigators didn’t buy his explanation. They say enhanced video showed Mehserle reaching for the gun several times, and looking at the weapon as he finally drew it.

“It makes me frustrated, because if you look at that, the officer already has 7 complaints against him that year, and nothing was done. And it just goes back to the frustration level of – there is no accountability for police officers,” said Johnson.

The report also criticizes a second BART officer – Anthony Pirone – saying he was aggressive throughout the encounter, using the n-word, punching and kneeing grant as he was forced down onto the platform.

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Bart released a statement saying in part, “Since the tragedy, BART and its police department have worked diligently to ensure that our officers receive the proper training, support and oversight necessary to respond appropriately and effectively to challenging situations.”

The records were released under California’s new police transparency law.

Read the full report from BART.
Pirone told investigators he had scuffled with Grant but the report says video of the Fruitvale Station encounter shows Pirone struck Grant in the head and kneed him, likely causing injuries documented in his autopsy. It adds that Grant did not fight back.

“Pirone was, in large part, responsible for setting the events in motion that created a chaotic and tense situation on the platform, setting the stage, even if inadvertent, for the shooting of Oscar Grant,” said Kimberly Colwell and Jayne Williams, the attorneys who authored the report dated July 31, 2009.

Colwell and Williams cited Pirone’s “repeated, unreasonable and unnecessary use of force,” his “manifest lack of veracity” and his use of a racial slur while arguing with Grant in recommending the officer’s firing.

Pirone was not criminally charged.

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© Copyright 2019 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.