PART 2: The NM-DPS Crime Lab—
Misrepresentation of DNA Contamination Errors
Since launching Spence Forensic Resources (SFR) in February 2008, I have reviewed over 250 forensic biology/DNA cases originating out of the New Mexico Department of Public Safety (NM-DPS) Crime Lab. This facility is located in Santa Fe, New Mexico. Beginning in late 2016, I have provided reports, pretrial interviews, and testimony, regarding the failure of NM-DPS Crime Lab management to effectively address the chronic, unnecessary risks of DNA contamination events persisting within their casework. At the center of these risks is the lack of separation of time and space between known DNA reference samples, and samples from vital evidentiary items. In light of the fact that—in recent years—an abundance of DNA contamination Corrective Action Reports (CARs) have been documented within the NM-DPS Crime Lab facility, it is alarming that so little progress has been made—toward actually correcting these potentially catastrophic lapses.
The blueprint for addressing contamination problems is readily available within the FBI document entitled: “Quality Assurance Standards For DNA Databasing Laboratories.” The September 2011 version of these FBI QA standards has been updated—as of July 1, 2020. Crime Lab management across the U.S. must adhere to Standard 7, entitled “Facilities and Sample Control”. Within section 7.1.3, the FBI emphasizes the risks associated with “amplified DNA product”. Best practices for handling DNA processing steps, and amplified DNA, have been elegantly defined within the January 12, 2017, document published by the Scientific Working Group on DNA Analysis Methods (SWGDAM). This document is entitled: “Contamination Prevention/Detection Guidelines For Forensic DNA Laboratories.” Specifically, lab managers within all forensic DNA testing facilities should embrace SWGDAM Guideline 2.1.2, which unambiguously advises as follows: “Reference samples should be processed separately from evidentiary items by area and/or time.”
The specific case investigation that prompted the publication of this article can be described as follows: Mr. Guillermo Hernandez-Lara was accused of sexually abusing a young female. The alleged incident in question occurred on June 4, 2016. On November 9, 2016, one lab report was released by the NM-DPS Crime Lab. The reporting analyst is referred to here as Ms. RSK. Technical review of Ms. RSK’s report was conducted by another crime lab analyst, who is referred to here as Ms. RA. In October 2017, I began my examination of the NM-DPS forensic biology/DNA case file relevant to the sexual abuse allegations that targeted Mr. Lara. A copy of the NM-DPS Crime Lab case file, number 16-3571-DPS, can be requested for review.
Within Ms. RSK’s bench notes, Page 43 displayed the capillary electrophoresis (CE) egram printout from STR testing of ‘reagent blank sample-9939’. Anytime that such a ‘blank’ sample is typed for DNA, there needs to be zero indications of any genetic signals on the egram. Contrary to this fact, the RB-9939 negative control sample clearly revealed a DNA contamination profile. Over 25 genetic signals were readily observed on this document. Based upon my examination of over 250 NM-DPS Crime Lab cases, additional troubling abnormalities were apparent within Ms. RSK’s case file. These were as follows:
1) NM-DPS Crime Lab analysts routinely enter handwritten notes—directly onto their egram printouts—calling attention to any unanticipated features, such as typing artifacts, off-ladder signals, elevated stutter signals, pull-up signals, DNA mixtures, and of course, any instances of suspected contamination. Despite the multitude of irrefutable contamination peaks on the RB-9939 egram, the only notation on this printout was a handwritten “43”—the page number;
2) Similar to all case files generated within the NM-DPS Crime Lab, Ms. RSK’s documented steps were technically reviewed by one of her peers—Ms. RA. Regardless of the unmistakable presence of the unexpected allelic information on this negative control egram, there is no record indicating that Ms. RA expressed any doubts associated with Ms. RSK’s results. Furthermore, there is no record of any formal discussions between Ms. RSK, Ms. RA, and/or NM-DPS Crime Lab management—regarding this disturbing contamination failure;
3) Managers with the NM-DPS Crime Lab have a history of routinely encouraging CAR reports for all contamination events. These CAR reports include Root Cause Analysis documentation of any incident—as well as an inquiry into the probable source of the contaminating DNA. Despite these traditionally followed, sensible quality assurance practices, no CAR report was ever filed, corresponding to Case File 16-3571-DPS, or the source of the RB-9939 contamination event. It was an elementary exercise to align the observed RB-9939 contamination alleles with the known DNA profile from Mr. Lara. There is absolutely zero doubt that the accused man was the source of this contamination!
On April 19, 2022, 5½ years after the release of Ms. RSK’s case report, her sworn testimony was provided at Mr. Lara’s trial. This proceeding was held at the Third Judicial District Court, located in Las Cruces, New Mexico. In order to review the pre-trial/trial events, please refer to: New Mexico v. Guillermo Hernandez-Lara, Cause Number: D-307-CR-2016-00826.
During the direct examination of Ms. RSK, Mr. Arif Abrar—the Assistant District Attorney responsible for the prosecution of Mr. Lara—asked his witness about the Page 43 egram. Ms. RSK testified as follows: “So, this is the electropherogram or the data that came off of my negative reagent control. And it should be completely blank.·However, you can see that there are some peaks that are showing up here. However, because they are below my analytical threshold, I do not know if it's actual DNA or if it is instrument noise.·So, at this point, this is considered a clean reagent blank as per laboratory's standard operating procedures.” Mr. Abrar: “So, these peaks that you see, did the machine alert you when you are doing the testing that there has been some kind of contamination that has occurred?” Ms. RSK: “Sir, this is not considered a contamination, because none of these peaks are called.” This nonsense defies all standards of logic. Considering that crime lab managers/analysts furnish themselves with the convenience of calibrating analytical thresholds for ‘calling’ or ‘not calling’ their egram peaks, a simple act of perjury paves the way for crime labs to pretend that no contamination errors are ever on a given egram printout.
During cross-examination, counsel for the defense revisited the RB-9939 contamination peaks, asking: “But isn’t it remarkable that all of these peaks tend to match up with Guillermo Hernandez-Lara's peaks?” Ms. RSK: “I don't know how you would arrive at that conclusion, sir. None of these [peaks] are being called. There are known artifacts that can produce that.·There are things called spikes and pull-ups; and then there are other flecks that might cause the instrument to register it as peaks when there aren't any DNA peaks. And that’s the whole reason that we establish the analytical threshold, because under that–below that threshold, we don't know if that is real DNA or not.” Defense Counsel: “Okay.·So, it could be DNA, right?” Ms. RSK: “Absolutely, yes.” Defense Counsel: “Okay, and that would be a big problem, wouldn't it?” Ms. RSK: “Yes, sir. If they were called and it was DNA, then it would be a problem and it would result in a corrective action.” When defense counsel questioned Ms. RSK regarding the fact that the twenty-five+ RB-9939 egram signals were never mentioned in her NM-DPS Crime Lab report, she presented the following response: “Because, again—it’s not contamination. It’s not required, sir.” Again, such testimony is the equivalent of collecting droppings from a farm animal, topping them with whipped cream, and attempting to pass them off as “dessert”.
During my testimony, Mr. Abrar seemed offended by my assessments—suggesting that crime lab managers had condoned COVERING UP the obvious contamination error. He asked—in the event that this atrocity was so indisputable—why haven’t any derogatory findings ever emerged during the crime lab audits? Specifically, the ADA questioned why I had voiced no reports of my concerns to the accreditors responsible for the NM-DPS Crime Lab.
Guillermo Hernandez-Lara was convicted. Six and a half months later, on November 3, 2022, I did indeed report the facts of this case—including the crime lab contamination risk issues—to the American Association for Laboratory Accreditation (A2LA). This is the organization responsible for renewing the accreditation of the NM-DPS Crime Lab. During an early December A2LA assessor site visit, the NM-DPS Crime Lab was cited for a multitude of non-conformances, including various alarming contamination risks. The lab was also cited for failures to consistently address DNA contamination errors—through implementation of effective CARs.
On January 31, 2023, my contact at A2LA emailed me a confirmation, proclaiming that the lab site visit was complete, with assessors finding my complaint “...to be valid as submitted.” This A2LA email also emphasized that: “...we have cited non-conformances that will require corrective action before we renew the NM-DPS lab’s accreditation.”
During early 2023, NM-DPS Crime Lab management was able to secure extensions on their accreditation renewal. Rather than the customary few weeks, it took the facility five months to *finally* achieve a 4-year renewal of their A2LA accreditation. NM-DPS Crime Lab management doubled down, emphasizing their denial that any DNA contamination crisis had ever occurred. A July 20, 2023, Albuquerque Journal article was released, bearing the title: “Forensic Lab Reaccreditation Confirms Its Unbiased Expertise”. NM-DPS Crime Lab management boasted that their “...standards of excellence are attained and maintained.” They also alleged that “...forensic scientists perform meticulous work, provide unbiased analysis and laboratory reports, and testify as expert witnesses in their scientific discipline.”
It is always troubling when errors are committed by individuals who have been entrusted with sophisticated resources—such as DNA technology. However, a profoundly deeper social plague emerges when an ethos of arrogance, denial, and misrepresentation pollutes the deployment of those formidable resources, and the sworn testimony that follows.
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