District Attorney Chesa Boudin held a press conference on Feb. 3. Photo by Eleni Balakrishnan.

When sexual assault victims provide DNA to help prosecute their case, they’ve long been assured that their sample will be destroyed immediately afterward. But, according to a new discovery by the San Francisco District Attorney’s Office, the SFPD has been retaining victims’ samples indefinitely, and potentially using them to charge sexual assault victims with unrelated crimes.

“We want to protect the privacy of the sexual assault survivors, and we want them to feel comfortable coming forward. The last thing we want to do is expose them to further trauma,” said District Attorney Chesa Boudin this morning at a roundtable discussion. 

Boudin said his office last week became aware of a case in which a woman who submitted her DNA following a sexual assault was being charged with a felony in a property crime based on that DNA sample.

If a victim is potentially opening themself up for criminal charges down the road, the DA says this would provide a disincentive for them to provide DNA samples. “Charging and prosecuting these cases will be all the more difficult,” he said. 

Generally speaking, victims of sexual assaults undergo exams to collect biological evidence. The collected sample, called a “rape kit,” will contain DNA from both the perpetrator and the victim, which must be separated by the crime lab of the local police department, according to Kate Chatfield, acting chief of staff of the District Attorney’s Office.

As for the sexual victim, Boudin said “Her attorneys are aware of it. I can’t speak to what she personally knows.”

Given this development, the District Attorney’s Office is evaluating whether it’s possible to excise the problematic evidence and still prove the property crime case. “If the answer is yes, then we try to proceed with what we’ve got there,” said Boudin. 

The District Attorney’s office today said it does not know how often this has occurred previously. “We’re dealing with many thousands of instances a year in which unknown suspects’ DNA is tested against a Quality Assurance database, including all sexual assault survivors,” said Boudin. It remains unknown whether children’s DNA is also kept in the databases.

Under the Fourth Amendment, law enforcement must obtain a warrant or written permission from a court to lawfully seize evidence. And, in this case, “It’s very clear that they’re not consenting to their DNA being collected to use five, 10, 15 years later on in a law enforcement investigation,” Boudin said.

Marsy’s Law, the California Victims’ Bill of Rights Act of 2008, also states that the victims can expect “the prompt return of property when no longer needed as evidence.”

“As far as we understand, these DNA profiles are saved uniquely in the quality assurance database. They are not going to be uploaded into a broader statewide or national database. That’s good. But it’s not enough,” said Boudin. “Because they’re still being used for purposes at the local level unrelated to investigating or prosecuting the underlying sexual assault.”

Multiple messages for the San Francisco Police Department have not been returned. According to Boudin, Chief Bill Scott “did not seem to be aware of” this issue.

So far, the District Attorney’s Office hasn’t begun assessing similar practices elsewhere, which will require the cooperation of the SFPD in identifying cases. “A lot of times, the chronological investigation we received is pretty opaque about which database was searched. My hope is that they have detailed records that they’ll share with us, and we can look backwards,” said Boudin.

The District Attorney’s Office will be holding a general press conference on this issue tomorrow at 10:30 a.m. 


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REPORTER. Yujie Zhou is our newest reporter and came on as an intern after graduating from Columbia University's Graduate School of Journalism. She is a full-time staff reporter as part of the Report for America program that helps put young journalists in newsrooms. Before falling in love with the Mission, Yujie covered New York City, studied politics through the “street clashes” in Hong Kong, and earned a wine-tasting certificate in two days. She’s proud to be a bilingual journalist. Follow her on Twitter @Yujie_ZZ.

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  1. A disturbing (illegal?) and, sounds like, longterm practice. According to what I’ve been reading in SF papers, it might (will likely) be difficult to obtain cooperation from the SFPD. Many procedures that are supposed to protect seem to be allowed to become loose ends, thereby jeopardizing process and accountability. Damn shame.

  2. This is vile but what can we expect from SFPD at this point? I’m not surprised, just disgusted and angry. At least we know Boudin’s office isn’t buckling under the pressure from the POA, this will for sure undercut the Chief and the Mayor when they ask us to believe them on matters of public safety.

  3. This sounds to me like Boudin is suddenly “shocked” by this revelation. If it is not illegal, and I assume it’s not or the police would never risk their jobs by doing it, then the police can and have been doing this for a long time. I would guess it’s a standard procedure. While I agree it is counter-productive to the goal of ensuring victims of sexual assault who may also be involved in criminal activity come forward to submit to bio-testing, I doubt this information is some kind of revelation to Boudin. But that’s what spin is all about.

  4. This is a terrible dilemma. While protecting sexual assault victims from secondary trauma brought about by “naming and shaming,” I think we can all agree that the chance to apprehend a perpetrator of a serious crime using DNA may, under certain circumstances, outweigh the interest of further victimization.

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