The Colorado Bureau of Investigation (CBI) today announced the findings of an internal affairs investigation into a former CBI DNA scientist accused of data manipulation of DNA test results.
A thorough internal investigation initiated in September 2023, has revealed that Yvonne “Missy” Woods manipulated data in the DNA testing process, posting incomplete test results in some cases. 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 brought in third-party investigative resources to protect the integrity of the inquiry.
“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.”
A separate criminal investigation initiated late last year in the Woods matter is still underway. CBI continues to cooperate with our law enforcement partners across the state.
In addition to these ongoing efforts, CBI is currently engaged in a comprehensive audit of all DNA analysts to ensure the accuracy and completeness of its entire catalog of records. The audit will ensure compliance with CBI’s policies and procedures and laboratory integrity.
CBI will continue reviewing and instituting improvements to lab policies and testing protocols to prevent this type of manipulation from occurring in the future.
CBI Forensic Services has maintained regular communication with its accreditation body throughout this entire process. This collaboration and transparency has ensured the actions have not affected the CBI's accreditation status.
In the course of our exhaustive audit and review process, CBI discovered indications that an analyst employed by the Weld County Sheriff’s Office at the Northern Colorado Regional Forensic Laboratory may have also manipulated DNA testing data. CBI referred this case to the Weld County Sheriff’s Office for further investigation. This case is separate from the Woods case.
Highlights and timelines from CBI’s internal investigation can be found below.
Internal Investigation of Yvonne “Missy” Woods Highlights
The CBI Internal investigation, dated February 26, 2024, determined that Woods:
- Omitted material facts in official criminal justice records
- Tampered with DNA testing results by omitting some of those results
- Violated CBI’s Code of Conduct and CBI laboratory policies ranging from data retention to quality control measures
In September 2023, CBI became aware that DNA sample testing performed by Yvonne “Missy” Woods, a 29-year veteran of the CBI crime lab, may have deviated from standard operating procedures.
On October 3, 2023, Woods was placed on administrative leave, and an internal investigation was initiated by CBI Director Chris Schaefer. Woods performed no additional laboratory work and retired on November 6, 2023.
As part of the internal investigation, CBI collaborated with members of the Kansas Bureau of Investigation to ensure independent evaluation of the scientific and technical issues involved.
From October 3, 2023 to present, CBI’s Quality Management team has been reviewing all of Woods’ work. At this time, 652 cases have been identified as affected by Woods’ data manipulation between 2008 and 2023. A review of Woods’ work from 1994 to 2008 is also underway.
CBI’s DNA forensics team identified the following types of manipulation in Woods’ work:
- Deleted and altered data that concealed Woods’ tampering with controls
- Deleted data that concealed Woods’ failure to troubleshoot issues within the testing process
- Failed to provide thorough documentation in the case record related to certain tests performed
These manipulations appear to have been the result of intentional conduct on the part of Woods.
The review did not find that Woods falsified DNA matches or otherwise fabricated DNA profiles. 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. The CBI has a high degree of confidence in its analysts and laboratory integrity and the level of ongoing scrutiny is high.
Based on the results of this investigation, CBI is evaluating and implementing process and procedural changes that will enhance the integrity of its testing processes and their results. CBI will provide more information regarding these changes once this process is complete.
Because this is an active criminal investigation no further information can be provided at this time.