Dakota County District Judge Kathryn Davis Messerich ruled that a second batch of test results on drug evidence first examined at the troubled St. Paul police crime lab can be admitted in court.

Public defender Lauri Traub had argued that the samples, retested by the Minnesota Bureau of Criminal Apprehension, could have been contaminated at the police lab because of poor workplace practices, poor equipment maintenance and staff's failure to follow basic scientific procedures.

Messerich issued her decision Friday, ending a nearly yearlong probe into the police lab's operations, which have led to major overhauls at the lab and a review of drug cases before three county attorneys.

"In summary, the testimony of these witnesses supported the possibility of contamination rather than the actual presence of contamination," Messerich wrote in her decision. "The State has met its burden here because a jury could reasonably conclude that the evidence came into and left the [police lab] in the same condition."

Traub said she was disappointed with Messerich's decision, but thankful that the questions she and former public defender Christine Funk raised last year led to changes at the police lab.

"Look at what happened because we had this hearing," Traub said. "Everybody found out about the problems with the crime lab and the crime lab realized it needed to make improvements and it started doing that."

Messerich wrote that "there were not substantial differences" between how police lab criminalists and BCA forensic scientist Eric Grunwald handled evidence and cleaned their work stations. Defense attorneys attempted to raise skepticism about how the police lab, which is not accredited, handled those tasks. Grunwald retested the drug evidence in the three Dakota County cases, and testified on behalf of the prosecution.

Traub said the comparison wasn't equitable, because BCA scientists are better trained than the police's criminalists.

The Police Department immediately stopped all drug testing when testimony started last July, and plans to fund two people at the BCA, which is accredited, to test future drug cases. Independent audits commissioned by the city supported defense expert witness testimony that the lab was not properly run and that staff who tested suspected drugs were not properly trained. Three people who tested drugs at the police lab have been laid off.

Police expect to reopen the crime lab as early as June 15, said police spokesman Howie Padilla. The lab will conduct crime scene processing, latent print processing and DNA collection. The department is "satisfied" with the judge's decision, Padilla said.

Earlier this year, the department hired new civilian manager Rosanna Caswell to oversee the lab. Caswell, who worked for more than a decade in the accredited lab at the Arizona Department of Public Safety, hopes to have the lab apply for accreditation by the end of the year.

Messerich's decision only has direct impact on the three cases in Dakota County and has no value as a precedent, although attorneys could choose to reference it in future filings. About two dozen drug cases in Ramsey County District Court are being challenged due to information that came out during several days of testimony in the Dakota County case.

"It's definitely going to have an impact in that there'll be an expectation that Ramsey County will go the same way" as Messerich, said Ramsey County public defender Jeffrey Benson, who is representing some clients contesting their cases.

In a few weeks public defender Jenny Chaplinski and her team of law clerks will finish an initial review of 1,700 cases tested by the police lab they pulled for possible post-conviction relief. Chaplinski said Messerich's decision won't affect her work.

"We are not going to go away and say, 'Nevermind. This is enough,' " she said.

The BCA retested 197 drug cases first tested by the police lab. The BCA's results contradicted police results in three cases, resulting in the dismissal of one case in Ramsey County.

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