SFPD chief sheds light on rape kit DNA allegations, says suspect also IDd on criminal database

SFPD Bill Scott and District Attorney give a joint press conference before a feud erupted between the two top law enforcement officials. 

San Francisco Police Chief Bill Scott on Wednesday pledged to investigate allegations the city crime lab used DNA from a rape kit to identify a criminal suspect – while explaining that the unnamed suspect’s DNA was found in a "quality assurance" database before it came back as a match in a criminal database. 

District Attorney Chesa Boudin dropped the bombshell allegations earlier this week, while questioning whether there was widespread practice of using rape victims DNA to identify them in criminal cases.

At Wednesday's Police Commission meeting, the chief was clear that the quality control database was not a lone match for the suspect's DNA profile. He also revealed that investigators had reported the match in the so-called "quality assurance" database, as well as the match in the criminal database, to prosecutors in December before an arrest warrant was issued. 

Even so, the chief said the practice of using DNA from a rape kit – even for quality control purposes – was concerning and pledged to investigate the crime lab’s policies. 

"I understand the importance of this matter," Scott said. "We will look into our practices. We will reform what needs to be reformed. But there’s a lot more to this that needs public transparency."

Boudin has not elaborated on the case at the center of the controversy. He said the suspect was arrested in a property crime case and had submitted to a rape kit examination back in 2016. 

Boudin did not mention that the suspect's DNA had also matched on a criminal database. He said he’s since dropped the charges against the suspect. 

The district attorney's office did not respond to questions from KTVU.

Chief Scott said the crime lab maintains a quality assurance database in order to identify potential contamination before DNA profiles are run in databases like federal Combined DNA Index System – or CODIS.

The CODIS database contains profiles from people arrested for felony offenses that can be referenced by law enforcement organizations around the country. 

The chief said the quality assurance database contains DNA profiles from lab personnel, visitors and profiles that are produced inside the lab – like crime victim DNA from rape kits.

It’s unclear why a DNA profile from a rape kit from 2016 would need to be in a database used to identify contamination. 

The chief said he’s working to get to the bottom of what happened.

"How do we make sure that those DNA samples that aren’t used to identify or used in criminal matters unrelated to the very reason that they’re in there, particularly in terms of sexual assault?" Scott said. 

The chief did not indicate that any suspect has been identified though the quality assurance database alone or if the issue was more widespread. 

Evan Sernoffsky is an investigative reporter for KTVU. Email Evan at evan.sernoffsky@foxtv.com and follow him on Twitter @EvanSernoffsky