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Former CBI scientist accused of manipulating data in 652 cases, internal investigation finds

CBI released its findings from the internal affairs investigation on Friday morning. A criminal investigation is ongoing.
CBI_Yvonne Woods
Posted at 11:51 AM, Mar 08, 2024
and last updated 2024-03-09 00:23:24-05

LAKEWOOD, Colo. — A former forensic scientist with the Colorado Bureau of Investigation (CBI) altered and deleted data in DNA testing in hundreds of cases, according to an internal affairs investigation.

The internal investigation into Yvonne “Missy” Woods began in September 2023 and its results were announced by CBI on Friday morning. Woods worked for CBI for about 29 years and left the agency in November 2023, just before CBI publicly announced that it had discovered the anomalies.

Results from the investigation, released Friday morning, determined that Woods omitted material facts in official criminal justice records, tampered with DNA testing results by omitting some results, and violated CBI’s Code of Conduct and CBI laboratory policies, according to CBI. As of Friday, the agency had found more than 650 cases impacted by her alleged tampering.

She is accused of:

  • Deleting and altering data that concealed how she tampered with controls
  • Deleting data that concealed her failure to troubleshoot issues within the testing process
  • Failing to provide thorough documentation in the case record related to certain tests performed

CBI officials said the manipulations appear to have been intentional. They did not list a motive.
"This discovery puts all of her work in question, and CBI is in the process of reviewing all her previous work for data manipulation to ensure the integrity of all CBI laboratory results," CBI said in a news release, adding that a third-party was brought in to investigate Woods' work.

Denver 7+ Colorado News Latest Headlines | March 8, 11am

This case began in September, when CBI learned that DNA sample testing by Woods may have deviated from standard procedures. By early October, she was placed on administrative leave — where she was not allowed to perform laboratory work — and the internal investigation began. She then retired in November.

From Oct. 3, 2023 to March 2024, CBI’s Quality Management team reviewed Woods' work. As of Friday morning, 652 cases were impacted by her data manipulation between 2008 and 2023, CBI officials said. Investigators are looking into her work from 1994 to 2008.

"The review did not find that Woods falsified DNA matches or otherwise fabricated DNA profiles," CBI said. "She instead deviated from standard testing protocols and cut corners, calling into question the reliability of the testing she conducted. According to CBI’s policies and procedures, Woods should have conducted additional testing to ensure the reliability of her results in these affected cases."

During this process, CBI discovered that an analyst employed with the Weld County Sheriff’s Office at the Northern Colorado Regional Forensic Laboratory may have also manipulated DNA testing data. This case — which is separate from the Woods case — was referred to the sheriff's office for an investigation.

Denver7 news partners at The Denver Post found that retesting DNA samples in thousands of criminal cases will cost at least $7.5 million, according to a state budget request.

In addition to this internal affairs investigation, a separate criminal investigation began late in 2023. That investigation is ongoing.

CBI_Yvonne Woods

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Denver7 obtained a statement from Woods' attorney, which reads that she was a loyal and dedicated forensic scientist for almost three decades.

It continues:

"While the allegations resulting from the internal investigation alleged that (sic) Ms. Woods deviated from standard protocols and cut corners in her work, the findings of the internal investigation support Ms. Woods earlier statements she’s never created or reported any false inculpatory DNA matches or exclusions, nor has she testified falsely in any hearing or trial resulting in a false conviction or unjust imprisonment. To the extent that the findings of the internal investigation calls into questions the rest of her work over 29 years with the Colorado Bureau of Investigation Ms. Woods will continue to cooperate with law enforcement to preserve the integrity of her work that resulted in true and just criminal justice findings – whether arrests, convictions or exonerations."

CBI is working on a comprehensive audit of all its DNA analysts, and officials said the agency will continue to institute improvements to its policies and protocols to prevent this from happening again.

“Public trust in our institutions is critical to the fulfillment of our mission,” said CBI Director Chris Schaefer. “Our actions in rectifying this unprecedented breach of trust will be thorough and transparent.”

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