In its 66-page report, an independent police oversight and review group found a Vallejo police ffficer's use of force was not objectively reasonable when he shot and killed Sean Monterrosa through the windshield from the backseat of unmarked police vehicle.
"They got it right you know that what Officer Jarrett Tonn did to Sean is not right and is not correct and it violated the department's policies," said Michelle Monterrosa, Sean's sister.
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"It just proved what we all knew from the jump," said Ashley Monterrosa, Sean's sister.
A lawsuit filed by the Monterrosa family names the officer as Jarrett Tonn, though to this day the police department has not named him.
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Monterrosa was outside a Walgreens on June 2, 2020 where there had been a looting during a protest over George Floyd's murder by police.
Vallejo police said Monterrosa was crouched down in a half kneeling position, moving his hands towards his waist area revealing what appeared to the officer to be the butt of a handgun. It turned out to be a hammer.
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The report found Monterrosa's action was potentially consistent with an intent to surrender. Something his sisters have said all along.
"Sean knew if he was in any danger or in a situation like this you get on your knees and raise your hands up as a universal sign of surrender," said Ashley Monterrosa.
"This is something we're all taught," said Michelle Monterrosa.
The report also revealed the fatal shot entered the back of Monterrosa's head, inconsistent with officers' statements that he was facing them in an aggressive shooting stance at the time.
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While officers are not expected to be absolutely sure of a threat before using deadly force according to the report, the second guessing by the officer who shot and killed Monterrosa suggested significant uncertainty about whether Monterrosa was carrying a gun. That uncertainty was captured by the officers' body worn cameras.
"What did he point at us," the officer could be heard asking.
"I don't know man," another officer replied.
"Hey, he pointed a gun at us," shouted the first officer.
The report also highlighted when officers started their recordings and found they could have safely begun recording sooner. The delay prevented capturing audio of the actual shooting.
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"When they're called to show up on scene from that moment they get that call from the dispatchers they should automatically turn on their cameras," said Ashley Monterrosa.
The report found the officer who shot Monterrosa violated the department's de-escalation policy.
In a statement, the Vallejo Police Department said the disciplinary process is robust and lengthy, defined by city rules and state law. Also that the department has made significant changes and improvements to its policies and procedures especially around de-escalation.
An attorney general's office independent review to determine whether criminal charges should be filed against the officer is ongoing.