Castile, who is black, was killed following a July 6 traffic stop.
The cop who fatally shot Philando Castile this summer before his girlfriend livestreamed the gruesome aftermath has been charged with second-degree manslaughter.
Prosecutors in Minnesota on Wednesday announced the charges against St. Anthony police officer Jeronimo Yanez, who shot Castile during a traffic stop in the St. Paul suburb of Falcon Heights July 6.
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The case made instant headlines, in part, because Diamond Reynolds, who was in the car along with her young daughter at the time of the shooting, posted a disturbing Facebook Live video of her dying boyfriend.
Reynolds said Castile was shot several times while reaching for his ID after telling Officer Yanez that he was armed and had a gun permit.
Members of Castile's family believe he was the victim of racial profiling.
Yanez's attorney said his client was reacting to the presence of a gun after pulling Castile over because he believed his description matched that of an armed robbery suspect.
On Wednesday, prosecutors revealed they disagree.
"Based upon our thorough and exhaustive review of the facts, I have come to the conclusion that there simply was no justification for the use of deadly force by Officer Yanez in this case. No reasonable officer who knew, saw, and heard what Officer Yanez did at the time would have used deadly force under these circumstances," Ramsey County Attorney John Choi said in a statement.
Choi said Castile was not a suspect in the armed robbery.
He said the case is a way to seek justice for Castile, as well as for Reynolds and her daughter.
In addition to the manslaughter charge, Yanez has been charged with two additional felony counts of Intentional Discharge of a Dangerous Weapon for allegedly endangering the safety of Reynolds and her 4-year-old daughter.
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"I ask for the public’s continued patience, trust and respect for the integrity of the process as we prosecute this case and seek justice for Philando Castile, his family and friends, including Diamond Reynolds and her daughter, and our broader community," Choi said.
Yanez will face a judge Friday at 1:30 p.m. in Ramsey County District Court.