Investigation: ‘Gold Standard’ Of Evidence Turned To Pyrite By Colorado Crime Lab Employee
from the looks-like-law-enforcement-can't-be-trusted-to-handle-evidence dept
Law enforcement investigators and prosecutors have overwhelmingly embraced plenty of pseudoscience over the years, treating everything from bite marks to hair samples as conclusive evidence capable of singling out guilty parties.
Most claims were specious, backed only by “expert” statements from law enforcement crime lab employees solely interested in confirming prevailing law enforcement theories. And that’s when things are on the up and up. In multiple cases, forensic scientists and other crime lab employees have faked tests and falsified evidence to cover up everything from laziness to their own illegal drub habits.
DNA has long been considered the evidence no one can question. But it’s far from fallible. DNA indicates little more than something exists where other people exists. DNA is prone to cross-contamination — something that led law enforcement on a years-long pursuit of a nonexistent serial killer before investigators realized the DNA found at multiple crime scenes was actually that of the person packing the swabs investigators used when examining crime scenes.
Multiple factors make DNA far less reliable than it’s portrayed in popular media. DNA can be taken from one scene and deposited at another. Exclusion-focused tests can result in false positives simply by deciding the most common DNA at the site is an indicator of guilt. The lack of rigorous, consistent standards across all law enforcement agencies means a lot of so-called “evidence” derived from DNA at crime scenes is mostly the result of a forensic examiner’s interpretation of the data, rather than an empirical conclusion based on standardized best practices.
Then there’s things like this, where whatever value DNA evidence might have had was destroyed by lab misconduct, as Emma Tucker and Andi Babineau report for CNN.
A now-former forensic scientist with the Colorado Bureau of Investigation (CBI) manipulated or omitted DNA test results in hundreds of cases, an internal affairs investigation found, which prompted a full review of her work during her nearly 30-year career at the agency.
The CBI released the findings of the investigation into Yvonne “Missy” Woods Friday, which concluded Woods’ handling of DNA testing data affected 652 cases between 2008 and 2023, including posting incomplete results in some cases. A review of her work from 1994 to 2008 is also underway, according to the CBI.
“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,” the agency said. “CBI brought in third-party investigative resources to protect the integrity of the inquiry.”
These weren’t the actions of a new hire who simply didn’t know what they were doing or thought the real purpose of their employment was to support whatever investigators suggested would be the proper conclusion. Yvonne Woods worked for the CBI’s crime lab for nearly 30 years before her malfeasance was uncovered.
And this isn’t even all of it. What’s detailed above only covers half her career. Another investigation is underway to look into the details of her first 15 years of employment by the state.
As for Woods, her lawyer insists this was nothing more than a bit of incomplete paperwork. Attorney Ryan Brackey claims Woods “never created or reported any false inculpatory DNA matches or exclusions.” Maybe so, but that’s not what the CBI’s investigation (performed in conjunction with the Kansas Bureau of Investigation) determined.
The agency said its forensics team discovered Woods deleted and altered data that served to conceal evidence of her tampering as well as her failure to “troubleshoot issues within the testing process.” The agency said Woods’ manipulations “appear to have been the result of intentional conduct.”
This says something else. It says tampered evidence made its way into court and that evidence of this tampering was covered up by the forensic scientist.
Woods’ attorney also claims she never “testified falsely” in any hearing or trial that resulted in a false conviction or wrongful imprisonment. And, sure, this could possibly be true. But if the state’s Bureau of Investigation has already found 15 years of wrongdoing (and is currently digging into the other 15 years), the only way this assertion could be considered true at this point is if Woods never offered testimony during criminal proceedings.
And that’s obviously not the case:
Boulder District Attorney Michael Dougherty told CNN in a statement his office has identified 15 open cases and 55 closed cases in which Woods has testified as a witness.
One lawsuit naming Woods as part of the chain of events leading to the wrongful imprisonment of a man has been filed. With the results of the first half of the CBI’s investigation being made public — along with the date range and approximate number of cases affected — there will certainly be more to follow.
DNA’s only as good as the people examining it and the processes they follow. In the case of Woods and the CBI crime lab, this evidence doesn’t even begin to approach anything considered to be a “gold standard.” Instead, it’s just one thing to be manipulated in favor of law enforcement or, at best, something to be handled as carelessly as routine clerical busywork.
Filed Under: colorado, colorado bureau of investigations, dna, evidence, yvonne woods


Comments on “Investigation: ‘Gold Standard’ Of Evidence Turned To Pyrite By Colorado Crime Lab Employee”
drub habits?
I thought the drubbings only happened on the street during the arrest.
Re:
The drub habits will continue until morale improves.
Re:
No, the deaths of ‘excited delirium’ happen on the street during the arrest. The drubbings happen in the cells if the police actually succeed in getting a suspect there without killing them.
DNA and science
This is crucially important to recognize. While the forensic use of DNA is the only field in forensics that was developed by actual scientists, rather than law enforcement and their allies, and it has been subjected to rigorous analysis and extensively peer reviewed, it is, again, only as good as the people examining it and the processes they follow.
Superficial DNA "Matches"
I don’t know where to begin. Based on my experience with DNA testing for genealogy, I strongly suspect that the so-called “CODIS” DNA markers used by police has ever been adequate to definitively declare a “match” between a suspect and some crime-scene DNA sample. If I am ever to be convicted of a crime based on a DNA “match”. I want to be on the basis of 111 Y-chromosome DNA markers, the full loop of some 16,000 mitochondrial DNA markers, and at least 2,000 centiMorgans of autosomal DNA. Anything less than that is insufficient evidence, in my view.
Re:
You have X chromosomes too, and not everyone has Y chromosomes.
Re: Re:
If he was ever convicted, why would he want a test on someone else’s X-chromosome???
Re: Re: Re:
Because he has XY chromosomes. Go take an elementary-level science lesson, dipshit.
Re: Re: Re:2 Glass Houses
You might want to look where you are before throwing stones. If someone has a Y, why would you not want to focus on that? Seems to me that based on elementary statistics, it would cut the pool of potential false matches in half. This is in the imaginary perfect science world of course. In reality, I have no knowledge of what the ratio of XY to the other karyotypes is in the data sets used. My gut says that the criminal databases are heavily weighted towards XY, while the genealogy databases are generally slightly weighted away.
Re: Re: Re:2
Do you even have a basic understanding what the XX/XY chromosomes denotes? Why would a man who is trying to prove his innocence use the X-chromosome? That other people also have an X-chromosome is an utterly useless statement given the context, plus you increase the pool of possible false positives.
So who is it that really needs to “take an elementary-level science lesson” here? It’s certainly not me.
Re: Re: Re:3
Oh, no reason really, only the fact that tests based on mitochondrial DNA give more accurate results than others. But you’re right about elementary school-level science, as mitochondrial DNA isn’t taught about until high school, clearly high above your level.
Re: Re: Re:4
I love the self-goals you did there by A) glossing over the fact that mitochondrial DNA (mtDNA) has nothing to do with XX vs XY, which was the point of the reply starting this thread, just so you can try to insult another’s understanding of biology, while B) ignoring that the OP included the full mitochondrial DNA loop in their lists of requirement for a DNA match so you are essentially arguing that matching a subset of data is superior to matching the full set. But you couldn’t stop there and had to go for the self-goal hattrick by C) implying that mitochondrial DNA matching is more accurate for the confirmation that a specific sample came from a specific XY individual over Y chromosome matching.
I will give you that mtDNA is more inherently stable so there is likely to be less degradation of a given sample so the test results will more accurately match the sample. But to say it is more accurate for matching a sample to a specific XY individual over a Y match completely misses the forest for the trees. The mtDNA chain is tiny compared to the nuclear genome. The Y chromosome consists of ~62.5 million base pairs vs ~16.6 thousand mtDNA, so the best p-value you can get for a mtDNA match is orders of magnitude worse than the best you could get for a full Y chromosome match. There is also the little fact that because of its stability, there is minimal variation in the mtDNA of matrilineal relations, which means the thing that makes it great for identifying ancestry does not make it great for identifying a specific individual. If you found my mtDNA at a crime scene, it could be mine, my siblings, my mother, my matrilineal grandmother, my matrilineal aunts, my matrilineal uncles, any cousins born from my matrilineal aunts, etc. In extreme cases, there are groups of 100+ living humans out there that would match solely based on mtDNA testing. This could also apply to Y-chromosome matching of patrilineal relatives if families have a lot of XY members, but since nuclear DNA mutates more than mtDNA my Y-chromosome is less of a a perfect match to my patrilineal relatives than my mtDNA is with my matrilineal ones.
Which gets back to the point of OP. They want a strong Y-chromosome match AND a full mtDNA match AND a match of over 25% of the rest of the chromosomes (full nuclear DNA chain is ~7400 centimorgans). At that point, you have limited your false positives to identical multiple XY birth siblings…
Re: Re: Re:5
The only own goal here is yours.
DNA has long been considered the evidence no one can question. But it’s far from fallible.
emphasis mine. infallible maybe? Being “far from fallible” strongly implies it’s infallible.
Re:
Chiming in to agree with this here.
It really does need to say “far from infallible” or the sentence says the exact opposite of what it is intended to mean in context.
“Law enforcement investigators and prosecutors have overwhelmingly embraced plenty of pseudoscience over the years …”
… but MUCH more significantly — JUDGES have also routinely accepted prosecutor/police pseudoscience at face value, ignoring Defendants rights to see the FULL basis of evidence against them as presented in court
A view from the bench
I have followed techdirt for a long, long time. One thing that they have covered too many times is these types of situations
Any result is only as good as the process that obtains it. Any process must be able to be duplicated by independent third parties. But that would cost money. Then maybe we should cut back on the over gathering of data; Data we have no actual legitimate use for. LEO love to hide the truth, because they have already made up their minds.
Re:
… yes LEOs generally tend to ‘hide the full truth’ to convict their targets — prosecutors & judges are usually well aware of this, but still treat LEOs as highly credible Expert witnesses
if it’s too difficult to verify the testimony of a LEO or supposed Expert Witness — that’s automatic Reasonable-Doubt of that evidence
if a JUDGE/JURY do NOT really understand the validity of technical evidence against a defendant — they must Acquit
the Gold Standard is innocent until PROVEN GUILTY to a jury in a fair trial
Wet cleanup aisle 2
Hey Davec ya boos dhat on the floor again. Get your broom and mop and try to defend this mess.
This comment has been flagged by the community. Click here to show it.
Resident disaffected blogger hates police and will seize any opportunity to attack them. We get it.
Re:
“We”, is it?
Tell us, was it a crushing blow when you flunked out of Trolling 101? Did you retreat to your mom’s basement and drown your humiliation with cheetos and diet mountain dew?
This comment has been flagged by the community. Click here to show it.
Re: Re:
lol. I’m still here. Steven T. Stone has quit the comments section. Clear W for me.
Re: Re: Re:
Resident anon loves the boot and will take any opportunity to deflect valid criticism against the boot, we get it.
I know you hate America, but as a proud American, I will support the honorable American tradition of lambasting authority that oppresses the common people.
This comment has been flagged by the community. Click here to show it.
Re: Re: Re:2
I appreciate “common people” (especially non-Whites) being oppressed and hassled by the police.
It makes my majority-White, solidly middle class town a much better place by disincentivizing scum from encroaching on the turf of us productive, property-owning folks.
This is also why I’m active in local politics and support Republican elected officials: keeps me pleasantly aligned with those who wield power on behalf of non-degenerates/non-progtards.
Re: Re: Re:2
A proud tradition that began in 1773. Oyez!
Re: Re: Re:
It was kinda cute the way you had such a crush on him.
Re: Re: Re:
I thought I made him implode when I asked to define a woman. How can a tranny be a woman if we can’t define what a woman is?
Re: Re: Re:2
WPATH Files
Re: Re: Re:2
You know, you’ve got a point. A tranny can never be a real woman. Wrong kind of tech. (Tranny = transistor radio.)
Re: Re: Re:3
Tranny = transmission!
Re: Re: Re:4
Also transformer, Ford Transit, and photographic transparency.
Re: Re: Re:5
And none can be a woman until you define what a woman is. Simpletons
Re: Re: Re:6
We all know it’s not your narrow definition, though, transphobe.
Re:
Resident disaffected commenter hates people knowing about police misconduct and will seize any opportunity to attack those reporting on it. We get it.
There was recently a case in Germany, where a woman was falsy accused of murder because her DNA was found at the scene.
Turns out she had been there 3 days before the murder for a job interview. She also had an airtight alibi for the time of the murder but police and prosecuters didn’t care.
She spent 7 month in pretrial detention, during which her newborn child was seperated from her.
(Here an article in German https://www.ndr.de/nachrichten/hamburg/Mord-in-Borgfelde-38-Jaehrige-nach-monatelanger-Haft-freigesprochen,borgfelde114.html )
You don't 'accidentally' try to hide evidence tampering
I could see a handful of honest mistakes as over three decades even a job that should have the highest of standards is still going to have a few screw-ups, but when the person involved actively attempts to hide those ‘mistakes’ that rips away any shred of benefit of the doubt I might have been willing to grant.
Re:
what’s that old saying? the cover-up is always worse than the crime
Massive conspiracy anyone?
When one of these kinda situations come up, and it’s distressing how often they have, it makes me wonder about how it would go if they applied conspiracy laws as loosely and with as much abandon as they do in drug cases. If this woman worked on capital cases, it would be attempted or actual murder and I don’t believe NO ONE had any idea what she was doing, in 30 years?
Not Just Dishonesty
See this case:
https://www.cbc.ca/news/canada/manitoba/mark-grant-retrial-derksen-decision-1.4360436
The police were determined to find a perp (where have we heard this story before?) to solve the cold case.
They therefore found a crime lab that claimed to be able to create DNA profile for limitied partial DNA fragments. The lab analyzed the fragments supposedly found on the twine used on the victim, and surprise(!) they matched the guy being blamed for a 30-year-old murder.
(News reports were vague upon the details, but supposedly the lab worked with fragments and the match was partial, not the “one in a billion” level of odds that a better sample would provide.)
Of course, the police had been following the guy, and likely had some samples of his DNA; whether the lab made a mistake, was it wishful thinnking, or outright deception – who knows?
No controls, no audits?
30 years? Were there no controls, no audits? I don’t know anything about police labs per se, but I do know auditing the lab would have slowed her roll.
Re:
My thoughts exactly.
A lab should never know which case a DNA-sample belongs to, they shouldn’t either know the identity (or identities) of the matched profile(s). Those investigating the related crime should never be allowed to talk to lab-technicians either, unless it’s in court.
That way you can submit control-samples randomly to better evaluate the labs performance while also avoiding undue influence from LEO’s investigating a crime.
Re:
They can’t even be arsed keep breathalyzers calibrated, so, no.
The crime rate is so high in America because the police spend the vast majority of their time hunting down traffick viokators, and the police, sherrifs, and FBI waste the rest of their time creating victims and criminals in sting ooerations that they use as lame atrempts to justify their government jobs. They are burdens to society that are increasing the crime rate on purpose, the way that the mafia or street gangs do to demand people join the mafia or street gangs or pay the mafia to protect them.
Police, government, healthcare, and the surveillance state want to keep it a secret that they are an Orwellian Neo-Nazi terrorist network and organized crime ring that live Ted Bundy Joseph Mengele, Manson Family, Brach Davidian lifestyles so that they will have the element of surprise when they attack people like a school of pirhanaas like they have been doing to me for the past ten years.