Last month's passage of a THC driving bill, following two failed attempts, was achieved thanks to a language tweak that convinced one-time opponents to sign up. But might they have balked if they'd known about alleged problems at the state lab where the blood testing required by the new law will be done?

One marijuana advocate can't help wondering, especially since the report (on view below) wasn't released until Friday even though it was completed in March, during debate over the bill.

The bill sets an intoxication standard of five nanograms of THC (the active ingredient in cannabis) per milliliter of blood. Those who test over that number aren't automatically assumed to be guilty: The text's "presumptive inference" rule allows chronic users whose systems may register over that figure even when sober to argue in court that they weren't actually impaired.

But the law still puts a great deal of weight on blood test results to be generated by the state toxicology lab, operated under the auspices of the Colorado Department of Public Health and Environment and, until recently, overseen by Cynthia Burbach.

The rub? As Alan Predergast reported yesterday, defense attorneys held a press conference yesterday to complain about the tardy release of a report on the lab by the Mountain States Employers Council, which "delves into employee concerns about inadequate training, unsafe storage of evidence, understaffing, supervisor bias" and other concerns.

The investigation was actually completed in March, but wasn't made public for months -- and was only shared after supervisor Burbach had retired.

Suthers insists that there was no foot-dragging when it came to issuing these details. In a statement circulated after the press conference, he said in part, "The details of this personnel report involve a complex intersection of various laws, including civil, privacy and employment laws. Once prosecutors in my office became aware of the potentially mitigating nature of the information contained in the Mountain States Employers Council report, I immediately acted to ensure its expeditious release."

Attorney Rob Corry, among the most vocal critics of the THC driving bill, isn't buying it.

"There's no question in my mind that somebody sat on that report," Corry says. "I don't know who, but the report was known to the government, and it should have been known to the legislature, it should have been known to opponents, and it should have been known to the general public."

Continue for more of our interview with Rob Corry, including photos and documents. According to Corry, Burbach was a familiar presence at the legislature during the debate about the THC driving bills that were introduced (and fell short) in 2011 and 2012. However, her profile was much lower this time around.

"We were all wondering where she was, because she'd been so aggressive during the past efforts," he notes. "And now we know. I've faced her in court many times, and she had strong opinions, which we disagreed with. But now it looks like those opinions might have been questionable."

Corry can't say with certainty that the THC bill would have failed had the report about the lab been available to lawmakers before the final vote was cast -- "but the legislature obviously has the power to repeal laws it has previously passed, and that's an option for next session." More immediately, though, "I think there will be a slew of defense lawyers filing motions in hundreds, if not thousands, of DUI cases throughout the state -- cases where people either pleaded guilty because Ms. Burbach was listed as a witness or people went to trial and were convicted based on her testimony."

Additionally, Corry believes that alleged problems at the lab will be cited in litigation down the line. "That's going to be a common feature of every trial in the future for years to come," he allows. "I think it would be remiss for any defense lawyer not to question the reliability of evidence brought forth by the government.

"It's always been clear to a lot of us that the supposedly non-biased, scientific players were very interested in the results of trials, and that they appeared to have maybe an emotional or professional interest in convicting people. It was abundantly clear by their demeanor and behavior throughout these cases, both pre-trial and during trials, and this report confirms that."

Could the government drop some cases already in the pipeline and be more cautious about new prosecutions because of doubts about the lab's reliability? "If the government wants to back off, that's their option," Corry replies. "We're in a defense posture. Our obligation is to bring justice for our clients. The government has to decide which cases to pursue -- and to pursue them with hard evidence.

"There are still a lot of unanswered questions. But if our state lab can't be trusted to measure nanograms in blood accurately and in an unbiased fashion, then the entire system that they're trying to create through this five-nanogram presumptive inference law is in doubt."

Continue to see the report, followed by a release from the Colorado District Attorneys Council arguing that the lab's results can still be trusted.

More from our Colorado Crimes archive: "Photos: Tour Denver's new $28 million crime lab."

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