Yvonne “Missy” Woods, a former Colorado Bureau of Investigation forensic scientist at the center of the CBI DNA scandal, pleaded guilty in June 2026 to four felonies after investigators found she had deleted, altered, or omitted DNA data in more than 1,000 criminal cases over a 29-year career. Her misconduct has vacated at least one murder conviction, forced prosecutors to offer reduced plea deals in homicide cases, prompted reviews of thousands of cases statewide, and led to a new Colorado law on forensic integrity.
What Woods Did to the DNA Evidence
Woods worked as a DNA analyst at the CBI from 1994 to 2023 and handled more than 10,000 cases, testifying in some of Colorado’s highest-profile trials. Investigators found she deleted and manipulated DNA quantification values, re-ran testing batches without documentation, and concealed potential contamination.
In more than 30 sexual assault cases, she deleted values showing small amounts of male DNA and then reported “No Male DNA Found,” avoiding the follow-up testing those results would have required. Told by internal affairs investigators to explain, Woods said she had been on “a rush batch” and was “trying to get data out.” She said she had no “good reason” for the manipulation and told investigators she deleted male DNA findings in sex assault cases “because it was easy.”
The CBI’s internal review found that Woods deviated from protocols, deleted data, and concealed her tampering, but did not fabricate DNA profiles or falsify matches. Her misconduct did not create false identifications. It meant testing that should have been done was skipped or hidden, potentially letting guilty people escape prosecution and depriving defendants of evidence that could have cleared them.1
How the Misconduct Was Discovered
A CBI intern reviewing historical sexual assault files in September 2023 spotted missing quantification data in DNA test records. An internal affairs investigation opened October 3, 2023, and Woods was placed on administrative leave the same day. She retired on November 6, 2023, before the investigation closed.
The Kansas Bureau of Investigation was brought in on November 1, 2023, to assist. The South Dakota Division of Criminal Investigation opened a separate criminal investigation on November 7, 2023. On June 5, 2024, CBI released a 94-page internal affairs report confirming Woods had “omitted material facts in official criminal justice records” and “tampered with DNA testing results by altering or omitting data.”
The 2023 discovery was not the first warning. A coworker raised concerns about Woods’ testing with a technical leader as early as 2014. In 2018, Woods was directly accused of data manipulation, removed from casework, and reviewed. She was reinstated, and the matter never reached the CBI Director or Colorado Department of Public Safety leadership. CBI has since opened additional investigations into why the 2018 accusation was not acted on.
How Many Cases Were Affected
CBI reviewed 10,786 cases Woods handled and found problems in 1,045 of them, roughly 10 percent. Sexual assault cases accounted for nearly half of the flagged files. The confirmed misconduct spanned 2008 to 2023, with an additional review going back to 1994. Fraudulent reports were sent to 24 Colorado law enforcement agencies.
The Denver Police Department launched an independent review of 422 sexual assault evidence kits handled by Woods, later expanded to more than 1,300 cases dating to 2013. Denver stopped sending sexual assault cases to CBI for testing in 2024. State budget documents estimated $7.5 million for the initial response, covering retesting, district attorney case reviews, and preparation for retrials. CBI estimated that 3,000 cases would need retesting by a third-party lab at roughly $1,000 per case. Overall fiscal cost has been estimated at more than $11 million.
The Criminal Charges and Guilty Plea
On January 22, 2025, First Judicial District Attorney Alexis King filed 102 felony charges against Woods, tied to 58 alleged instances of criminal misconduct between 2008 and 2023: one count of cybercrime (a class 2 felony for causing more than $1 million in damage to a computer system), one count of first-degree perjury for false testimony in a 2014 jury trial, 48 counts of attempting to influence a public servant, and 52 counts of forgery for false lab reports.
Woods pleaded not guilty to all 102 charges on February 11, 2026. On June 23, 2026, she changed her plea and pleaded guilty to four felony counts, one of each charge type. Prosecutors dismissed the remaining 98 counts. The plea agreement guarantees a prison sentence and eliminates probation, which Colorado law would otherwise have allowed for some of the offenses. Woods faces 8 to 16 years in the Department of Corrections. Sentencing is set for September 8, 2026.
King said the plea reflected “the full scope of criminal conduct that spanned decades” and that “securing a term of imprisonment, protecting the interests of the community, and our shared expectations of integrity in the justice system is reflected in this resolution.”
Consequences for Convictions and Prosecutions
The most prominent case affected is that of Michael Clark, convicted in 2012 of the 1994 murder of Marty Grisham in Boulder. Woods had tested a Carmex lip balm container from the scene, and her analysis was central to the case. Independent retesting after the scandal produced results inconsistent with Woods’ findings, indicating it was statistically more likely that someone other than Clark contributed the DNA. A judge vacated Clark’s conviction in April 2025, and he was released after more than 12 years of a life sentence. Boulder County District Attorney Michael Dougherty announced plans to retry him. The defense filed a 72-page motion in May 2026 seeking permanent dismissal, citing due process violations, a 32-year delay, and destroyed evidence. Clark remains free on bond.
In at least three murder cases since Woods’ arrest, prosecutors have offered defendants lesser charges and lighter sentences rather than risk trial with evidence tainted by her involvement. One involved Michael Jefferson, charged in the 1985 killing of Roger Dean; prosecutors offered a reduced plea because Woods’ DNA analysis was deemed potentially unreliable. Tamara Harney, Dean’s daughter, agreed to the deal to avoid a trial that could collapse. She said of Woods: “She’s affected so many people.”
Challenges are also moving through Colorado courts in homicide, sexual assault, and robbery cases. The Korey Wise Innocence Project at the University of Colorado Boulder School of Law is reviewing multiple cases. Staff attorney Jud Lohnes said Woods “doctored testing results to avoid testing,” depriving defendants of “DNA testing that could have proved their innocence” and causing victims’ cases to “wither on the vine.” Lohnes said some affected defendants never received notice from prosecutors because the information “got lost in the shuffle in CBI’s review.”
Reforms at CBI and in Colorado Law
Governor Jared Polis signed HB25-1275, the Forensic Science Integrity Act, on June 2, 2025, after the Colorado General Assembly passed it unanimously, 65-0 in the House and 35-0 in the Senate. The law requires crime lab employees to report known misconduct or significant events to a lab director within seven days, requires district attorneys to notify affected defendants and victims when misconduct is confirmed, and creates a legal pathway for individuals to seek post-conviction relief when forensic misconduct was material to their case. It also required retroactive review of misconduct investigations dating to July 2014.
A July 2025 independent audit by Forward Resolutions found systemic problems at CBI including “inadequate accountability, poor internal culture, a focus on productivity and gaps in crisis response.” The audit recommended separating forensic services from the CBI’s law enforcement function, potentially as a standalone division under the Colorado Department of Public Safety, to protect scientific impartiality. That reorganization would require new legislation and could take more than a year. CBI has hired additional DNA analysts and firearms examiners and is auditing the work of all its DNA analysts.
CBI Director Armando Saldate called Woods’ guilty plea “an important moment of accountability” and said the agency is focused on “moving forward” with reforms. Anyone who believes their case was affected is directed by CBI to contact their legal counsel or the district attorney’s office where the case was tried.