Inside the investigation of a CBI scientist’s years of misconduct: “God forbid we have someone in prison that shouldn’t be”

Everyone knew Yvonne “Missy” Woods worked fast.

The Colorado Bureau of Investigation DNA scientist made her way around the state laboratory in a walk-run, a signature forward-leaning gait. She handled two and three times as many cases as other analysts, worked the maximum 40 hours of overtime a month. Spent nights, weekends on the clock.

And for nearly 30 years, she reaped rewards: accolades and awards, high scores on performance evaluations, assignments to the state’s most high-profile criminal cases. She was the matriarch of CBI’s DNA lab, the go-to expert, an intimidating, entrenched force of a scientist who was frustrated with slower-paced colleagues, with people who insisted on following every little rule.

Former CBI Director John Camper called her an “all-star.”  One supervisor dubbed her a “workhorse.” She was one of the highest producers across the entire law enforcement agency.

And when her colleagues at the Arvada CBI lab raised red flags about the quality of her work, about how working fast had become working rushed, they were largely brushed off, considered complainers and pot stirrers.

“They say it is quality over quantity, but sometimes it doesn’t feel that way,” CBI DNA analyst Katrina Gomez told internal affairs investigators in December. “I don’t know if that was the fuel to her fire, right? ‘I keep getting accolades, I keep getting recognized because I keep pumping out cases.’ But then at what point does the system take a step back and say, ‘How is she doing so many?’ Or do they just turn a blind eye because they enjoy the fact she is doing so many cases?”

The Denver Post obtained more than 800 pages of CBI investigative documents and 10 hours of internal employee interviews that lay bare how Woods took advantage of the state lab’s focus on results and productivity — and professional trust between colleagues — to hide her widespread manipulation of DNA data.

She leveraged her high regard at work and intense personality to bypass protocols, cover up her alleged misconduct and dodge questions when colleagues raised concerns about her work in 2014 and again in 2018, the investigative materials show.

“I often wondered how she could be so efficient, and I had always asked her to help be a part of teaching the new scientists that we were hiring to be that efficient,” Jan Girten, now-retired deputy director of CBI Forensic Services, told internal affairs investigators. Woods always refused to help with training, she added.

“At the time I thought she just didn’t want to help, you know, not being a team player with management, even though she got frustrated at the slow ones, but now… I’m like, maybe she was jacking with us all along,” Girten told investigators. “And it’s just really sad. It’s really sad. It will blemish us.”

CBI leaders began to discover the full scope of Woods’ misconduct in late 2023. The agency found Woods cut corners in much of her DNA testing, then covered up her shortcuts by altering, deleting or omitting data from lab work. The agency has so far identified problems in 809 of Woods’ cases between 1994 and 2023, and state lawmakers set aside $7.5 million to remedy the wrongdoing.

Colorado’s criminal justice system is bracing for a slew of people challenging their criminal convictions based on Woods’ flawed work. Already, one man says he was wrongfully convicted of murder based on Woods’ faulty DNA testing, and prosecutors in Boulder said a triple murderer received a plea deal with a lighter sentence in part because of her misconduct. Woods’ flawed testing will seed doubt deep into Colorado’s criminal justice system for years to come.

Woods’ attorney, Ryan Brackley, did not comment for this story but in the past has maintained that Woods never created false DNA results or offered false testimony in court. CBI spokesman Rob Low declined to comment and, with the exception of Camper, everyone else named in this story either declined to comment or could not be reached for comment.

CBI officials last year quickly recognized the potentially massive ramifications of Woods’ misconduct and worked to protect their lab’s professional certification and the agency’s reputation, the material shows.

“God forbid we have someone in prison that shouldn’t be…” Assistant Director of Investigations Kellon Hassenstab told Woods in November. “We’re all crossing our fingers and toes that we don’t… because I don’t know how we would come back from that as an organization.”

A Friday afternoon confrontation

Late on a Friday afternoon in July 2018, CBI forensic scientist Kiffin Champlin reviewed Woods’ DNA work on a cold-case triple homicide.

Woods sat a few desks away, waiting for Champlin to finish so she could call the investigators before the weekend and tell them the 1984 “Hammer Killer” mystery was finally solved.

But Champlin found a problem: evidence of contamination in the sample, which should have required more testing — and more time — to address. And then she saw Woods had deleted data to make it appear as though the sample wasn’t contaminated, to eliminate the need for those additional steps.

“I was pissed,” Champlin told internal affairs investigators in November. “I was super angry… I’m like, that’s not an accident.”

She turned to her colleague, forensic scientist Jennifer Dahlberg, for a second opinion, and Dahlberg reacted with alarm.

“She’s done this before,” Dahlberg remembered saying. “And this needs to escalate now.”

Dahlberg had four years earlier, in 2014, reported a similar problem with Woods’ work to the lab’s DNA technical leader, Sarah Miller — the manager responsible for supervising the science side of the Arvada lab. At the time, Miller simply required Woods to fix the problem in that case, then moved on without further scrutiny.

That didn’t sit well with Dahlberg, who tried to distance herself from Woods in the following years. In January 2016, she met with two lab supervisors to go over a list of problems she perceived in the lab’s DNA testing and quality control.

The first line of her list reads: “Problem — Poor quality of work.”

Then, in bullet points: “Everything is rushed. People don’t take pride in their work.” “Everything is ‘good enough,’ not best practice.” ” ‘Hippie lab’ — everyone does what they want, too much analyst discretion.”

The list continues with seven specific examples of DNA analysts’ recent mistakes — including one by Woods — and ways the processes and training could be improved.

The managers blew her off, Dahlberg told investigators, and she was instructed to better her communication with Miller. Weeks later, Dahlberg voluntarily took a demotion and a pay cut to stop handling DNA for CBI, instead focusing her work on blood testing.

She hoped the problem she saw in Woods’ work in 2014 was a one-time issue. But when Champlin turned to her on that Friday afternoon in 2018, that hope was dashed.

“I truly hoped that if it was on purpose she would have stopped, but then at that moment I knew she hadn’t,” Dahlberg said during a December interview with internal affairs investigators.

When Champlin confronted Woods about the deletion in the triple-homicide case, the senior DNA analyst looked back at her “like a deer in the headlights,” Champlin told investigators. Woods didn’t say much. Silence and obfuscation were her go-to responses to confrontations about the quality of her work over the years, the internal materials show.

Champlin cried on the drive home out of frustration and anger, and spent that weekend screwing up the courage to report the incident to the lab’s higher-ups, vowing not to let Woods “commandeer her” before she could do so.

On Monday morning, Champlin went straight to Miller and Aaron Koning, CBI’s assistant director of quality for Forensic Services, and detailed the issue. She suggested a procedural change to ensure Woods couldn’t make similar deletions going forward.

She told another supervisor that Woods “should never touch evidence again,” but she didn’t want to see Woods fired.

This time, the lab’s supervisors did take action. They interviewed Woods about the deleted data. She said she wasn’t sure how it had happened, and that she was overwhelmed at work, handling too much and feeling burned out.

They removed Woods from casework and reviewed everything she’d done so far that year, about six months of DNA testing. Several people in the lab felt at the time that the data deletion couldn’t be an accident, but Miller — the sole person responsible for reviewing Woods’ prior work — was not convinced.

“Because I knew Missy for so long, I didn’t think that she intentionally did anything,” Miller told internal affairs investigators. “…I trusted what she was saying, in that it was a mistake and that’s how it was. She didn’t have a history of lying to us by any means. I wouldn’t have expected that. And it was such a weird thing that I’d never seen before. In talking with other managers it was like, ‘What is this? It must have been a fluke situation.’ ”

Miller found no other deletions in her review of Woods’ work, which she estimated took a few days. The lab’s supervisors sent Woods to counseling and stopped her from working overtime. After about three months, Woods returned to casework in November 2018. She started working overtime again in December 2018.

The way the inquiry was resolved suggested to others in Forensic Services that supervisors suspected Woods deleted the data on purpose, Lance Allen, deputy director of Forensic Services in Grand Junction, told internal affairs investigators in February.

“I mean if it wasn’t intentional, why didn’t we just fix the process and not send her to counseling?” he said. “It felt like they knew it was likely intentional. She wouldn’t say it, but they felt it likely was. But it was a one-time thing. It was caught, it was not characteristic, (so) we’re gonna address it this way.”

Miller later said she didn’t make the procedural change that Champlin put forward because it seemed like an “overreaction.”

“Keeping that data, it seemed like something that we’d never needed to do before, never thought about doing, because we trust each other’s work,” she said. “And we follow the (standard operating procedures), and the SOPs say take that data and put it into here to work off of. It was like, ‘Oh, is this an overreaction to do a lot more work when it just didn’t seem necessary.’ ”

Champlin, who’d gone on maternity leave shortly after reporting the 2018 deletion, returned to find Woods back at work just as before.

“I just felt that no one believed me before, and I felt almost targeted a little bit as a pain in the butt, someone who is stirring the pot,” she told investigators. “I was pissed, super pissed.”

Right back on casework

Woods took the return to work as a stamp of approval.

“I figured CBI Forensic Services had investigated me, and then they put me right back on casework,” she told Hassenstab during her internal affairs interview in November. “So I’m thinking, ‘Oh, OK, well, I must not have done anything.’ ”

“I would just flip that,” Hassenstab responded. “I would say, ‘I just got away with this.’ ”

“Yeah,” Woods said.

Content warning: This audio clip includes an expletive

When the two-and-a-half-hour interview ended, Woods awkwardly joked with the investigators that she’d worn orange that day in case she had “to go to the penitentiary,” so she’d know how she looked in that color. A criminal investigation is ongoing but she has not been charged.

The 2018 review was the closest CBI came to discovering Woods’ misconduct before the 2023 revelations, but it wasn’t the sole incident that caused concern among her colleagues in the lab.

Woods regularly avoided the formal workflow for making corrections to her work, the internal affairs investigation found. CBI’s DNA analysts can make changes to their cases up to a certain point, and after that must ask an employee with higher-level clearance to make changes through a formal process.

At least once or twice a week, Woods went to one particular person with that higher-level clearance, forensic scientist Marko Kokotovic, and asked him to make changes for her without doing that formal documentation. He had “complete trust” in her and regularly agreed to do so, he told investigators in December.

“Honestly she was always very resistant to (the formal process),” Kokotovic said. “I would ask her to do it. She was always giving me a hard time of, ‘It’s so stupid, it’s just a little deletion, why waste all this time doing a correction when it just takes two seconds to delete this.’ It was pretty much always a time thing… She was a little bit more on the intimidating side. And she was always getting so much done that I didn’t want to hinder her progress, in a sense. So I was like, ‘You’re right, I’ll just do it for ya’ and it’s this tidy thing, moving on.”

Woods and other DNA analysts also manipulated the technical review process — what is supposed to be a random process in which analysts review each other’s work for accuracy — to ensure that their allies at work got their reviews, the internal affairs investigators found.

Champlin told investigators she purposely avoided reviewing Woods’ work after the 2018 incident. And some of the top performers in the lab would pass their work back and forth among each other for technical reviews, Miller said.

“You have your friends, and your friends don’t question or argue,” Miller said. “The technical review process can be very argumentative between analysts, where one person thinks it is this kind of sample and the other person thinks it’s this. There can be a lot of arguing. When you are doing it with your buddy, who kind of has the same thinking as you do, you don’t have as many problems, as much fighting over the data.”

Woods’ reputation in the lab and her personality might have helped push her work through the technical review process with less scrutiny, she added.

“She had a very strong personality and a lot of experience, and we all really looked up to her,” Miller said. “And she’s not an easy person to challenge. Some things could have gone away because, honestly, cognitive bias could have been involved — thinking you trust what she is doing, she knows what she is doing, she’s been doing this for 20 years — and, ‘It’s OK, what I am reviewing, I am signing off on it.’ ”

Miller defended her 2018 review as aimed at catching Woods’ mistakes — not carefully hidden misconduct and data manipulation.

Purposeful misconduct like that is much harder to identify, Allen said.

“A quality system does a great job of catching unintentional errors and mistakes,” he said. “A quality system will never be able to always catch the intentional, malicious, deceitful acts of someone trying to hide things.”

Anger and accreditation

An intern at CBI stumbled onto the problems with Woods’ work in September 2023 while going through large amounts of data for a Loveland nurse’s proposed research project on whether the law enforcement agency should regularly start testing additional material in sexual assault cases.

It was routine data entry — until data was missing in one of Woods’ cases.

The intern alerted a supervisor, who alerted her supervisor, who investigated. The team quickly found additional examples of missing data and discovered the deletions were limited to Woods’ cases, not other analysts, the material shows. An initial review showed a wider pattern of deleted data across at least 30 of Woods’ cases.

CBI officials put Woods on leave nine days after the intern flagged the first case.

The agency’s leaders immediately recognized the severity of the problem, internal affairs records show.

“You can literally be the person whose work brings down CBI Forensic Services, and I’m not even exaggerating that,” Hassenstab told Woods in November.

“This is devastating for the agency,” Girten, the retired deputy director of Forensic Services, told investigators. “All these cases are going to come back to us, and they’ll get thrown out. … It’s going to wreak havoc on the criminal justice community in Colorado.”

CBI alerted its forensic services accreditation agency, the ANSI National Accreditation Board, to the situation on Nov. 3, saying Woods’ conduct called into question her integrity. The letter included more detail than CBI provided to the public three days later when it announced the investigation in a press release.

The agency has since provided monthly reports on the ongoing effort to fix the problems to the accreditation board, the materials show. A spokeswoman for the accreditation board did not return a request for comment on CBI’s standing.

Camper, who served as CBI’s director from 2018 to February 2023, told The Post in an interview last week — and internal affairs investigators in February — that he would have opened an investigation had anyone raised concerns about Woods’ work that went beyond an employee struggling with “personal issues” who needed to take time off.

“We certainly weren’t shy about opening up investigations for misconduct, and we opened up investigations for a hell of a lot less than that,” he told The Post. “If serious issues like that had been brought to our attention, by all means we would have investigated it thoroughly.”

He called Woods’ actions “extremely disappointing, extremely discouraging,” and said there was clearly a breakdown within CBI in how her case was handled.

“I think any employer wants personnel issues and performance issues to be handled at the lowest possible level — but that said, if there was that sense of frustration that things weren’t being addressed or taken seriously, then that is obviously something that CBI is going to have to ensure doesn’t take place in the future,” he said.

By the end of June, CBI had spent $59,000 of the $3 million it received in state funding to retest DNA samples that Woods handled, said Low, the spokesman. The agency is also administering $4.4 million to reimburse district attorney’s offices for work on wrongful conviction claims due to Woods’ work. So far only $1,900 of that money has been claimed, Low said, by the First Judicial District Attorney’s Office.

During the internal affairs investigation, Woods’ colleagues reacted to her conduct with anger, betrayal and bewilderment, their interviews show.

All recognized the long-reaching impact of her misconduct in Colorado criminal justice.

“Before… I would have said she was a good analyst, maybe not the most thorough,” Gomez said. “I would have said she cares about the case and the people associated with the case. But after learning the extent to which she altered her data, I have no words. …We sign a code of ethics, a code of conduct every year. These are people’s lives — you’re a public servant, you’re supposed to be doing your best to help these people. So I don’t understand how she thought it was OK to do what she did.”

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