San Francisco, CA— People charged with drug offenses in San Francisco may have their cases dropped or convictions overturned due to alleged evidence tampering and substandard conditions in the police crime lab, San Francisco Public Defender Jeff Adachi announced Wednesday.

Adachi called for an independent investigation one day after San Francisco police halted all drug testing at the lab amid allegations that Deborah Madden, a 29-year employee at the lab, stole and tampered with cocaine evidence on numerous occasions. Police also revealed Madden had a 2008 domestic violence conviction and is currently facing a weapons charge.

Approximately 20 public defender clients saw their felony drug cases dismissed Wednesday morning alone. Those arrested prior to 2008 may never be able to get a fair trial, since all drug evidence has since been destroyed, Adachi said.

Police and prosecutors never disclosed Madden’s arrests to the Public Defender’s office while continuing to call her as an expert witness at trials.

“We have clients who are serving time behind bars based solely on Ms. Madden’s credibility,” Adachi said.

Also on Tuesday, San Francisco police released a November audit by the American Society of Crime Laboratory Directors showing the laboratory lacks a secure chain of custody for evidence, fails to keep detailed case records and does not meet standards of cleanliness.

The revelations are the latest in a long history of problems within the crime lab, Adachi said.

  • In 1994, the crime lab came under scrutiny because a police lab technician allegedly certified evidence as illegal drugs without performing the required chemicals tests.
  • In 1996, the Civil Grand Jury issued a scathing report urging the lab to seek funds to hire additional staff and replace obsolete equipment in order to produce results that meet quality assurance standards.

Despite the crime lab’s history of misconduct and insufficient testing, police have refused to turn over any previous audits or documentation showing how lab workers achieved results in specific cases involving drugs or DNA, Adachi said.

“There must be a review from someone other than the police or district attorney’s office to ensure the lab is operating with transparency,” Adachi said. “This strikes right at the heart of justice in San Francisco.”