Updated

A former San Francisco lab technician who acknowledged snorting cocaine from evidence, resulting in the costly dismissal of hundreds of cases, will not be charged with a crime, state prosecutors said Friday.

The attorney general's office notified San Francisco police on Dec. 2 that there was not sufficient evidence to charge Deborah Madden, AG spokesman Jim Finefrock said Friday.

Madden, 60, had been accused of stealing small amounts of cocaine from the lab while working there last year.

The allegations led to the lab's closure in March and the dismissal of more than 600 drug cases. It also created a nightmare for District Attorney Kamala Harris, who asked the attorney general's office in April to handle any possible prosecution.

Madden's attorney, Paul DeMeester, said Friday his client is ecstatic.

"This lifts quite a burden for her," DeMeester said. "This is very positive news."

Public Defender Jeff Adachi said the decision raises concerns about a possible double standard when it comes to charging a police employee who acknowledged doing wrong.

"This scandal resulted in the dismissal of hundreds of cases and we're still reviewing thousands of others," Adachi said. "This has cost the city and county millions of dollars. The average citizen has to be scratching their heads on the rationale behind this.

"Somehow, I don't think we've heard the last of this."

Police Chief George Gascon said Friday that while he is "extremely disappointed," he respects the attorney general's decision.

"I'm not second-guessing the attorney general's office," he said.

Gascon said that after discovering the theft, he knew the lack of physical evidence could be a problem in prosecuting the case. The lab has since undergone several new procedures and was reaccredited earlier this month to do DNA and ballistics tests.

Drug testing is now being conducted in neighboring Alameda County.

Madden's behavior and job performance began attracting attention outside the lab late last year, according to records.

A top San Francisco prosecutor sent an e-mail to a chief assistant district attorney in November 2009 complaining about Madden's erratic behavior. The e-mail said Madden appeared to be purposely sabotaging cases by calling in sick on days she was to testify in court.

Police were tipped off to problems at the lab about a month later when Madden's sister notified Madden's direct supervisor that she had found a vial of cocaine on her sister's dresser in Madden's San Mateo home.

Madden acknowledged during a Feb. 26 police interview that she snorted cocaine that spilled on her work station to mask a drinking problem. She had taken a leave of absence when an audit revealed cocaine was missing from the lab.

Madden retired a short time later after 29 years on the job.

Harris, who will become attorney general on Monday, called the lab scandal a "fiasco."

DeMeester recalled that Madden was honest and forthright about all of the wrongdoing she had committed at the lab, which he maintains was "very minimal."

"I think the length of time in this investigation, as it dragged on, showed the weakness of this case," DeMeester said. "Had it been a slam dunk, they would've charged her in February or March. That was not the case."

Gascon, however, did leave open a slight possibility the case could be revisited.

"She admitted to the crime and we have sufficient evidence to believe that she committed the alleged acts," Gascon said. "But, again, I recognize the difficulty for the prosecutor to make a strong case out of it at this point."

Madden still faces felony charges for cocaine possession in San Mateo County. She has pleaded not guilty.

A hearing is scheduled in mid-January.