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A screenshot from a video of a Texas Forensic Science Commission meeting on April 20. During the meeting, the Commission adopted a report citing errors at a private Pennsylvania forensic laboratory. (Image: Courtesy of the Texas Forensic Science Commission)

The defense’s DNA data in a Washington, D.C. rape case was thrown out by a judge in 2015, due to technical errors by a Pennsylvania forensic laboratory.

Now the Texas Forensic Science Commission has cited the laboratory’s failings in an extensive report on the case, touching off a series of reviews and changes at the private lab.

The report has prompted a lab-wide review of about 1,500 DNA analyses handled by National Medical Services (NMS), Inc., a Pennsylvania-based forensic and medical facility, to see if “overblown data” may have affected other cases across the country. The NMS lab has agreed to a major “course correction” requested by the Texas forensic watchdog agency.

Part of that course correction involves two scientists specifically cited in the TFSC report. Both are no longer affiliated with NMS. However, both men are still part of the national forensic community’s standards-setting board: the Organization for Scientific Area Committees, or OSAC.

While a handful of government crime labs have been implicated in sweeping scandals over several years, the latest report is one of the few official actions taken against a private laboratory.

THE CASE, THE DNA

The case was U.S. v. Torney, a rape case in the nation’s capital. Cardell Torney was arrested and charged with sexual assault in 2012, about two years after an attack on a woman in the doorway of her home.

The DNA led to the identification and arrest of Torney, then 40—and was key to the prosecutor’s case, authorities said.

But a 2013 analysis of that swabbed DNA became the central debate of the case, early in the proceedings.

The public defender hired NMS Labs, of Willow Grove, Pa. They also enlisted the help of Phillip Danielson, a professor in the Department of Biological Sciences at the University of Denver.

Together, the NMS scientists used Promega’s PowerPlex 16HS System. Amid their amplification and interpretation of the genetic data, Danielson and scientists led by Christian Westring, then the head of the criminalistics section of the NMS lab, determined they had a DNA mixture. That mixture potentially included other men, based on the signals they interpreted.

The prosecution’s expert was Bruce Budowle, former FBI scientist and currently head of the Institute of Applied Genetics at the University of North Texas Health Science Center. Budowle’s interpretation was vastly different than that of NMS. Based off his findings, the state filed a motion to disqualify the NMS findings. Their contention was that the DNA had been amplified and then interpreted improperly, which muddled the results. A Promega expert on the technology also testified about NMS’s “misuse” of the technology, according to court documents.

The court agreed, contending that NMS did not follow its own protocols. At the time, the court described the testimony as “incomprehensible,” “uninformative” and “misleading,” and said that the lab “ignored its own validation data.” The court threw out the DNA results produced by NMS Labs, according to the decision in January 2015.

“NMS Labs’ application of its methodology and interpretation of the data generated by the testing was not conducted in accordance with accepted practices within the forensic DNA scientific community,” ruled Judge Herbert B. Dixon Jr.

‘OVERBLOWN DATA’

The TFSC launched an investigation into NMS and its cases in Texas last year. (Budowle, the prosecution’s expert on the Torney case, is a voting member of the TFSC, but recused himself on the matter.)

The TFSC conceded it doesn’t normally consider issues raised in a criminal case halfway across the country from Texas, but they were interested in determining the reliability of DNA cases by NMS in the Lone Star State, and elsewhere.

After months of investigation, the TFSC released its report on April 20. Their overall finding was that the DNA had been “overblown” and not performed according to standards in Torney, the report states.

Dilution and re-quantification of the original sample would have generated more reliable results, and an “excessive amount of template DNA (was) amplified,” it adds.

“The analyst followed NMS SOPs which did not require additional remedial steps,” according to the TFSC reviewers. “However, the final data as interpreted by the analyst was clearly unreliable as were the conclusions drawn from the data. This unreliable data was interpreted by the analyst and was reported to the client.”

That led to potential real-world implications. Since the NMS interpretation indicated a mixture with at least three contributors, it called into question the victim’s testimony that she had no other sexual partners around the time of the attack.

“In other words, the impeachment of the survivor’s testimony would be made possible not because of actual physical evidence of additional contributors, but because the laboratory used unreliable data to reach an incorrect conclusion regarding the number of contributors,” the TFSC adds.

NMS initiated a “major course correction” after the TFSC visited the site in December 2017, according to the report.

1,500 CASES

Those corrections included hiring Charlotte Word, a veteran DNA scientist, as a technical expert to re-investigate the DNA issues.

NMS has also reviewed all 88 Texas cases that were worked by the lab from 2010 to the present, according to the TFSC report.

NMS officials also committed to review 1,500 overall DNA cases the lab handled nationwide during the same time frame, said Barry Logan, the vice president for forensic science initiatives of NMS.

In an interview with Forensic Magazine, Logan said that the issue in Torney originally looked to be scientific disagreement between experts—but then proved to be systemic “issues” at NMS at the time.

But there was no malfeasance or misfeasance, he added.

“We felt at the time that the data we had, the validation that we had, supported the opinions that were given in that case,” said Logan. “After reflection, and following input from the Commission, we accept that it probably didn’t.”

The wholesale review, including all DNA cases stretching back to 2010, is two-thirds complete, and no further issues have been found thus far, according to Logan.

“We’re not finding any other instances of interpretation of overblown data,” said Logan. “And we’re not finding any other instances of analysts not feeling like they had a fair hearing of their opinions, or that they were overruled by supervisors—which were the two things that the Commission specifically asked us to look at.” 

In the course of review, NMS has also identified an unrelated Y-STR interpretation issue, which led to an incorrect exclusion of a person in a sexual assault case in Harris County. This problem involves an inhibitor in some commercial kits which, when combined with low-copy samples, can suppress findings, according to Logan. The problem is not exclusive to NMS—but has been identified and flagged by NMS and some others in recent literature, Logan added. 

The laboratory is also expected to provide quarterly updates about its progress in reviewing practices, according to the report.

“We’ve had a very good working relationship with the (Texas) Forensic Science Commission,” said Logan.

TWO EXPERTS

But the first part of the “course correction” at NMS cited by the TFSC is the separation between NMS and the two experts cited by the court in the Torney case, Danielson and Westring.

The former has not worked with NMS since Torney, and the latter is no longer an NMS employee, according to Logan.

Westring was an NMS employee until February, Logan said.  

Danielson and Westring both said they could not comment on the particulars of the TFSC report, since the Torney criminal case is still pending.

Danielson told Forensic Magazine he could not comment on a matter “still working its way through the courts.”

Westring ultimately maintained he would have to wait to comment further on the particulars of what the court and the TFSC called laboratory errors.

“This report deals with a disagreement between scientific experts—something that is not uncommon these days,” Westring said. “The underlying criminal case, however, is currently still working its way through the courts. Until this case becomes a settled matter, it would not be prudent for me to comment further on it.”

Both Danielson and Westring continue to be involved in the organization setting forensic science standards in the United States.

Both are still on OSAC and its various subdivisions, confirmed Rich Press, a spokesman for the National Institute of Standards and Technology (NIST) and OSAC. Danielson is on the Biology/DNA Scientific Area Committee, a post he has held since August 2014. Westring is on the Biological Data Interpretation and Reporting Subcommittee, where he has served since November 2014.

OSAC is aware of the TFSC conclusions—but no action has yet been taken, said Press.

“OSAC leadership is aware of the report’s findings,” he said in a statement. “OSAC leadership will determine whether any action is necessary.”

Also in the nation’s capital, the case against Cardell Torney still has yet to reach a jury. Trial is scheduled for August, according to a court docket report on the matter. The “overblown” data from NMS will not be part of the proceedings.

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