At a hearing, defense attorneys contended the lab's testing procedures threaten reliability in criminal cases.
The St. Paul police crime lab is under fire by two defense attorneys who allege its procedures are out-of-step with best practices, possibly endangering the reliability of drug tests in criminal cases across the east and south metro area.
At a Monday hearing, workers testified that the lab doesn't have written standard operating procedures, doesn't document when someone accesses its drug evidence vault and conducts no ongoing proficiency testing for staff.
"My concern is not just these eight cases," said public defender Lauri Traub, who along with Christine Funk recently filed a motion to scrutinize the lab's actions in eight cases Dakota County cases. "My concern is: Have there been people convicted on bad science or who pled? That should concern everyone."
The lab conducts tests for cases in Dakota, Ramsey and Washington counties, but it's unclear how a decision in this case could impact previous convictions or outstanding cases.
"It's too dependent on the judge's order," said Chief Deputy Dakota County Attorney Phil Prokopowicz. "You just don't know."
The Frye-Mack hearing requested by the public defenders seeks to determine whether scientific evidence can be used against a defendant by addressing two points: Is the technique used generally accepted in the scientific community? Was the test completed properly, following appropriate standards?
The motion was filed in May on behalf of Matthew D. Jensen, who was charged in 2009 in Dakota County with fifth-degree controlled substance, a felony, and possession of drug paraphernalia, a petty misdemeanor.
Traub and Funk trained their critique on the lab's lack of written standards for testing procedures, the absence of "validation" studies that ensure equipment is running correctly and possible contamination. The attorneys said the lab is not accredited, and under cross-examination, staff testified that there is no outside audit of its practices and staff skill levels.
St. Paul police spokesman Howie Padilla said there have not been any immediate changes to the lab, adding that the testing being questioned is a specific test, and just a small portion of the lab's work.
"As we understand, the issues surrounding the work of our crime lab are part of an on-going case, and at this time are awaiting a ruling by a judge," Padilla said. "We are not going to be addressing detailed aspects of that. However, what I can tell you is that Chief [Thomas] Smith has never made it a secret that if there are improvements to be made to the work being done by any aspect of our department, that he's willing to explore options to make improvements happen."
At Monday's hearing, criminalist Roberta DeCrans, who tested evidence in Jensen's case and determined that the substance was heroin, testified that she included unrelated test results in Jensen's file a handful of times. DeCrans told Traub those results were in the computer system before Jensen's tests, and that both sets of data printed together, but on separate pages.
"That's important because you disclosed someone else's file and it's now part of court record," Traub said.
"I guess that's true," DeCrans said.
"It just shows a lack of attention to detail," Traub said in an interview after the hearing.
DeCrans testified that the lab uses a gas chromatography-mass spectrometry (GC-MS) machine to analyze a substance's ions, which can help determine what kind of controlled substance it is. Traub noted that in one of Jensen's tests, the results showed an ion weight not seen in heroin.
Heroin is a "rude, crude" product that's often impure, DeCrans said, noting that other results supported her conclusion.
Traub asked if it could indicate that the evidence was another substance or that it was contaminated.
"I'm not saying I didn't consider it," DeCrans said. "Just with my training, that's what I thought and concluded."
Testimony will continue Tuesday and Wednesday. Seven other defendants' cases, under Traub and Funk, will be heard in August and September. Judge Kathryn Davis Messerich likely will issue a decision late this year.
Chao Xiong 612-270-4708 Twitter: @ChaoStrib