"They open up significant questions for me," said Gascón about the D.A.'s conclusions in light of available evidence.
Among the cases is the 2013 killing of Ricardo Diaz Zeferino by Gardena police. Officers believed he and two other men were suspects of a bicycle theft. But Zeferino's brother was the victim. Zeferino was not armed. After dropping his hands against officers orders, he's shot while his hands are down, palms facing out.
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"You can see somebody whose hands are coming down and he's shot and killed -- I find it offensive," Gascón said.
Gascón said he'd also reopen the investigation into Brendon Glenn's killing in Venice in 2015. For months, Katherine Mader, former LAPD inspector general and retired judge, and Je Yon Jung, senior trial attorney under President Barack Obama's civil rights division of the Department of Justice, reviewed dozens of cases, Gascón said.
During his time as San Francisco District Attorney he did not prosecute any officers who killed someone. But Gascón said there are distinctions.
"First of all, I've never had a case presented to me where the police shot an unarmed person... But in some cases, I came out publicly and said this is an unnecessary shooting," he said.
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The former Assistant Chief of the LAPD adds that as D.A. he'd also lobby for changes, advocating for a law that now limits the circumstances under which an officer can use lethal force. His open letter outlines the four cases he pledges to reopen, including the 2018 killing of Christopher Deandre Mitchell by Torrance police and the 2015 killing of Hector Morejon by Long Beach police, as well as his concerns about some ongoing investigations.
Lacey was not available for an interview. She told Eyewitness News in a statement:
"This move exposes George Gascon's inexperience as well as a complete lack of understanding of how our criminal justice system functions. Opening up old cases for political purposes will create a dangerous precedent. The voters should see this for what it is. A stunt, from someone who has never tried a single case. Prosecuting people in order to win votes is not something that should ever be done in any democratic country. Inappropriate use of a prosecutorial office creates major ethical dilemmas that will damage the reputation and the prestige of this office which should always be an independent, apolitical institution."
Gascón questions Lacey's ability to investigate these cases independently after receiving millions in campaign contributions from police unions.
"We see a continuous attempt to underline the facts that support the theory of the case of the police and completely ignore contradictory evidence," he said.