"I have assigned a team of lawyers to look back into the circumstances that caused the death of Oscar Grant. We will evaluate the evidence and the law, including the applicable law at the time and the statute of limitations, and make a determination," O'Malley said in a statement on Monday, adding that Grant's death "greatly impacted the county and the state."

Officer Johannes Mehserle shot Grant who was unarmed in the back on New Years Day as another officer knelt on his back. The officers were allegedly responding to calls about a fight on the train platform. 

Mehserle was able to avoid serious charges by claiming that he mistakenly thought his gun was a taser when he pulled the trigger, according to ABC affiliate 7 News. He only received an involuntary manslaughter conviction and served about 11 months in prison before being released in 2011.

Despite video of the incident showing Mehserle shooting Grant in the back, a judge ruled that he should be released early for good conduct, according to NBC News. Anthony Pirone, the officer seen holding Grant down during the shooting, was fired from the force but was never charged. 

O'Malley did not explain what the new investigation would entail, but in recent years more information about the case has been revealed by law firms and news outlets. Last year, the Associated Press released a report from a law firm that investigated the incident for the Bay Area Rapid Transit system. 

For years, Pirone has said that Grant tried to fight him and that was what led to the shooting. But video of the incident shows Pirone repeatedly punching and kneeing Grant, who did not hit back or respond. 

According to the Associated Press, Pirone "was, in large part, responsible for setting the events in motion that created a chaotic and tense situation on the platform."

The report found that Pirone was violent with Grant in a way that was deemed "repeated, unreasonable and unnecessary." The report also says Pirone used a slur against Grant before hitting him. 

In an interview with East Bay Times, family members of Grant said Pirone should face felony charges for his actions, but attorneys for Mehserle told NBC News that the statute of limitations may make it difficult for O'Malley to do anything significant. 

At a press conference on Monday, Grant's family held up photos of Minneapolis police officer Derek Chauvin kneeling on George Floyd's neck next to photos of Pirone and Mehserle on top of Grant. 

“We’re not holding our breath. But we definitely will be praying that she sees the truth in this issue,” Grant’s uncle, Cephus X Johnson, said about O'Malley. 

As Blavity previously reported last year, a large mural of Grant was created at Fruitvale Station where he was killed and a street was named after him. 

Oscar Grant honored with new mural and street signs outside the Fruitvale BART station ten years after his death. pic.twitter.com/cpyRikLLOT

— MoorInfo (@MoorInformation) June 12, 2019

In 2011, the Bay Area Rapid Transit agreed to pay Grant's daughter a settlement of $5.1 million, but the family has long sought charged against Pirone.

“Absolutely we are hopeful that Nancy O’Malley and her team will do the right thing, and the right thing is to convict Pirone for his actions in causing my son to lose his life and be killed,” Grant's mother, Wanda Johnson, said at a press conference on Monday, according to The East Bay Times. 

“Justice delayed is justice denied. We should not have to wait another 11 years…We were told then that it should happen, and it should happen now,” she added.