In an interview with ABC7 News, Boudin says it was a systemic failure.
Boudin says the San Francisco Police Department didn't notify parole in McAlister's most recent arrest on Dec. 20 and Daly City police didn't arrest McAlister after receiving a report that he may have stolen the car on Dec. 29. They also didn't contact parole according to the DA.
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"We need to work with the police and with all other law enforcement agencies that we partner with to do a better job at keeping the city safe. I can't do it without the police, they can't do it without me, and parole certainly can't do it if nobody even tells them somebody they supervise has been arrested. And that is exactly what happened here on December 20, and again with a different agency on December 29."
The state says they followed procedures and that no criminal charges were filed by the district attorney.
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Boudin is meeting with one of the victim's mother on Monday and believes the suspect could be arraigned in court as soon as Tuesday.
SFPD released a statement on Jan. 1 saying:
"At the San Francisco Police Department, our hearts go out to the families of the victims in last evening's fatal hit-and-run incident at Mission and Second Streets. This senseless tragedy shouldn't have happened. I commend the work San Francisco police officers have done to arrest and hold this individual accountable for his criminal conduct, and for the heroic work our members do every day on hundreds of cases like it. I'm also proud to lead a department that has been unflinching in embracing accountability. At the San Francisco Police Department, we take responsibility whenever we fall short of expectations. That's an approach every element of our criminal justice system needs to embrace. We must all be held equally accountable for the decisions we make, because they can have serious implications for the safety of those we serve. San Franciscans deserve nothing less, and that's what they're demanding from all of us in the criminal justice system."
You can watch his full interview with ABC7 News Anchor Dion Lim in the media player above.