The Colorado Bureau of Investigation allowed a longtime DNA scientist to stay on the job for years despite repeated concerns about the quality and reliability of her work, according to an internal report obtained Wednesday by The Denver Post.

The agency’s inaction allowed Yvonne “Missy” Woods to continue to mishandle DNA testing for nearly a decade after a colleague first raised alarm in 2014, until an intern rediscovered problems in 2023 and a subsequent investigation called nearly all of the scientist’s three decades of work into question.

The CBI has since found that Woods cut corners in much of her DNA testing and then covered up her shortcuts by altering, deleting or omitting data in her lab work. She also omitted relevant facts from criminal justice records and tampered with DNA testing by omitting some results, the bureau found.

The agency has so far identified problems in 654 of Woods’ cases between 2008 and 2023, and hadn’t yet finished a review of her cases between 1994 and 2008.

The CBI this year requested $3 million from state legislators to retest 3,000 DNA samples through a third-party laboratory, and sought another $4.4 million to pay out to district attorney’s offices across Colorado to address claims by people who say they were wrongly convicted because of Woods’ work.

Years of warning signs

Woods’ colleagues raised concern about the forensic scientist’s work in 2014, in 2018 and again in 2023, the internal investigation shows.

In interviews during the 2023 investigation, they described Woods as a “golden child” at the agency who “had management’s ear,” and as a high-producer who worked significant amounts of overtime. She was trusted with the CBI’s most high-profile cases.

But colleagues said she had a reputation among her peers for cutting corners in her work in order to stay on top, according to the report. They outlined several incidents over the years that raised doubt about Woods’ work but never led to her permanent removal from the job.

When a colleague discovered a problem in Woods’ work in 2014, a supervisor required Woods to fix it but took no additional action, the internal investigation found. In 2018, managers determined that errors in her work were “related to mental health,” according to the report. Woods claimed then she was “overwhelmed” by the amount of work she was assigned.

The forensic scientist was temporarily removed from casework, attended counseling and then returned to the job, though she was not allowed to work overtime for her first month back, according to the report. An internal review of her work at that time missed the larger pattern of Woods’ data manipulation across cases.

The agency is reviewing its response to the earlier complaints about Woods’ work, CBI Director Chris Schaefer said in a statement Wednesday.

“…We acknowledge that it took too long to detect ongoing intentional manipulation of our lab system,” Schaefer said. “We are in the process of identifying an external vendor to conduct an organizational review to ensure that our forensic services procedures and systems adhere to CBI’s high standards.”

The CBI on Wednesday released a redacted version of the report documenting its internal affairs investigation after initially refusing to make the 94-page document public because of the ongoing criminal investigations into Woods. The Post also obtained an unredacted copy.

Deleted DNA data

In a November interview with investigators, Woods admitted she deleted data about low quantities of male DNA in some sexual assault cases — especially cases from Denver police — so that she wouldn’t have to complete additional testing that was unlikely to produce conclusive results on those small genetic samples, according to the internal report.

Deleting the data likely allowed her to complete cases faster, because she didn’t have to continue “troubleshooting,” the report found.

She said she did it in sex assault cases “’cause it was easy,” according to a partial transcript of an interview she gave CBI investigators. She admitted she may have wanted to avoid questions from defense attorneys about why additional testing on the deleted samples was not done.

Woods told investigators she “didn’t even think about” the gravity of her actions until the start of the 2023 investigation, and that her thoughts when deleting the data were just “click done, move on, click done, move on.”

“It wasn’t until I left work that Thursday afternoon… that and I went — excuse me, but (expletive),” she said, according to the report. “What have I done?”

Woods also said she’d expected to be caught when concerns were raised in 2018. When the 2023 investigation began, she worried about going to jail, the internal report shows. She has not been charged with a crime but criminal investigations are underway.

In a statement Wednesday, Woods’ attorney, Ryan Brackley, said Woods maintains that she has not offered false testimony in court and her work has not led to any false convictions or imprisonments.

“While the allegations resulting from the internal investigation point to Ms. Woods deviating from standard protocols and cutting corners in her work, she has long maintained that she’s never created or falsely reported any inculpatory DNA matches or exclusions,” he said.

A 29-year CBI employee, Woods retired in lieu of termination late last year after the agency discovered widespread problems in her work.

“Deer in the headlights”

Woods told internal affairs investigators that the deleted and manipulated data was limited to sex assault cases, but accounts from her colleagues cast doubt on that claim.

In the summer of 2018, a colleague said she caught Woods manipulating DNA results in the case of Alex Ewing, the so-called “Hammer Killer,” who has since been convicted of murdering three Aurora family members and a Jefferson County woman in 1984. DNA was used to tie him to the crime scenes decades after the killings.

The colleague said Woods gave her the case around 2:30 p.m. on a Friday and demanded results by the end of the day. But the colleague found evidence of contamination in the DNA samples in the case, which would have required additional steps to address.

Woods then deleted data to make the sample appear uncontaminated, the colleague told investigators. The colleague confronted Woods and refused to sign off on the work, according to the internal investigation.

“Woods looked at her like ‘a deer in the headlights,’ ” the colleague told investigators. “(The colleague) told Woods she knew what she did, and she can’t cut corners.”

The colleague reported the incident to two supervisors, including the CBI’s assistant director of quality for forensic services. She was so troubled by it that she cried on the drive home from work that day, according to the report.

Later, Woods told the colleague she had completed the extra work on the case, and that she “wasn’t thinking clearly and was burned out.”

A supervisor later told the employee that the CBI “couldn’t prove what happened” and that no further action was taken. The colleague also said that the same supervisor had commented a couple of years ago that “it was too bad Woods has no integrity because she has plenty of experience.”

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