The video from the officer's body camera starts after Hannah Williams was pulled over for speeding.
After the officer's body camera initially starts recording, there is no sound for about 30 seconds.
Once the sound boots up, the officer can be heard instructing Williams to put her hands up.
The officer walks around the side of the car to find Williams out of the car, appearing to be in a shooting stance. That's when the officer opens fire and Williams falls to the ground.
Police say she was holding what turned out to be a replica gun. Another angle in the video shows what looks like a gun on the ground.
Police provided medical aid to Williams after the shooting, but she died from the gunshot wound.
Civil rights attorney Lee Merritt, who represents the Williams family, says they chose not to watch the video but he responded to what he saw.
"He came around the corner and saw a person in a shooting stance and it is difficult to make a split-second decision in that manner. We cannot exonerate him at this point, but we certainly can't condemn him," said Meritt.
Police also released a 911 call from Williams' father to report her and the car missing. He told the operator that Hannah was on anti-depressants.
The family also said the SUV she was driving was their rental car and that she took it without a permit or license.
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"One moment she's there, one moment she's gone. We don't deserve that, my parents don't deserve that kind of sadness," said sister Nyla Williams.
Merritt said Hannah was happy, surrounded by family when she took their rental car without a permit or license Friday night.
The Orange County District Attorney's Office is investigating the case and said her car and the officer's car made contact on the 91.
Merritt asserts her inexperience -- and potentially an earthquake -- contributed to the accident. He questions the credibility of witness accounts of what happened next.
"She brought her arms up, with a gun. Now, I don't know why," said witness Renay Arnold.
Merritt said it could've been her cellphone.
The D.A. released a photo of a replica gun found at the scene. Merritt said he doesn't believe it had anything do with her being shot.
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"The bodycam footage exists so that citizens, so that families, won't have to guess about what happens in a use-of-force incident," Merritt said.
The family plans to have an independent autopsy performed, Merritt said. He expects the results to be released soon.
The mayor of Fullerton released a statement late Thursday. The statement read:
As Mayor of Fullerton, I share the public's concern about the Officer involved shooting from Friday, July 5th. I understand the need for information and want to assure you that I have been in constant communication with Fullerton Police Chief Dunn about our internal investigation as well as the investigations by the Anaheim Police Department and the Orange County District Attorney's Office. For full public transparency and accountability, these investigations will be comprehensive, but they do take time to make sure all the facts are known.
I am also working with Chief Dunn to make sure that the release of video evidence, per Assembly Bill 748, is met, and in this case, exceeded, as the Fullerton Police Department will release relevant video evidence in the next few days.
Incidents like this are tragic for all involved. As a father, I empathize greatly with the sorrow and pain that the William's family is experiencing. I want everyone to know that releasing this information is very important to us, and to our continued commitment to accountability and transparency to the community we serve.