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D Magazine: Bad Blood at the Dallas County Crime Lab

by Andrea Grimes
  Published 8.24.2011  From D Magazine SEPT 2011


No matter how easy it looks on prime-time television, putting bad guys in jail isn’t as simple as slipping on a dark pair of sunglasses, coming up with a scathing quip, and having an invariably sexy forensic biologist deliver irrefutable evidence that eliminates all reasonable doubt. Forensic science is a lot

messier than that.

It’s so messy that, six years ago, Texas legislators created the Texas Forensic Science Commission. It was tasked with hearing complaints about faulty science, bad policy, and mismanagement in Texas crime labs, with an eye toward improving conviction integrity and ensuring the best possible practices in crime labs across the state.


The Dallas County Crime Lab—more formally called the Southwestern Institute of Forensic Sciences, or SWIFS—has yet to come under the commission’s microscope. But Dr. Chris Nulf says a thorough review is long overdue. He worked at the lab as a forensic analyst in 2008 and 2009 and has been trying to get the commission to investigate Dallas’ crime lab ever since. He is speaking openly for the first time about the problems he saw there during his tenure. Nulf says the lab practices poor quality control, training is sloppy, and management retaliates against employees who raise concerns. If Nulf is right and there are serious problems with the crime lab, every case that relies on physical evidence could be called into question. Imagine if every convicted rapist going back five years suddenly had a good reason to appeal his case. Similarly, sloppy lab work could send innocent people to jail.

“People’s liberties are at stake here,” Nulf says.


The Dallas County Crime Lab is currently accredited by the Texas Department of Public Safety and, as of 2003, by ASCLD/LAB, the multinational accreditation agency that crime labs pay to join. But Nulf says accreditation is only one part of the puzzle and that ASCLD/LAB has taken the lab at its word that its policies are sound. Essentially, the crime lab is doing fine because it says it is.

Nulf earned a Ph.D. in molecular microbiology from UT Southwestern Medical Center in 2004 and was hired on at the crime lab in March 2008. In the 14 months Nulf spent in training as a forensic analyst, he says that using expired chemicals was a matter of practice, that he saw a box fan used to cool a room where microscopic evidence was handled, and that he was trained under managers and supervisors who had different, and loose, interpretations of lab protocol.

“You never knew what to believe when someone told you something,” Nulf says of his training.


In the summer of 2008, Nulf informed his supervisor, Dr. Stacy McDonald, that a stock chemical, sodium perborate tetrahydrate, used in the serology lab—where blood and other bodily fluids are analyzed—had expired in 2005. The crime lab’s procedural manual states that that chemical can be used for a maximum of 90 days after its expiration date. When Nulf’s complaints were forwarded to ASCLD/LAB, the Dallas crime lab had an explanation. Management explained that sodium perborate is merely a component used to make complete “working solutions.” As long as the working solutions made from the expired chemical passed quality control, that was good enough. In other words, the lab admitted that, yes, it was using spoiled meat, but the chili still tasted fine.

Nulf claims that analysts were trained to re-prepare working solutions until they got a quality control that worked. If an expired chemical failed quality control most of the time but analysts could get it to work some of the time, no one would be the wiser. This kind of information wasn’t shared with ASCLD/LAB.


“They trained on preference, rather than protocol,” Nulf says. (Dallas County medical examiner Dr. Jeffrey Barnard, who oversees the crime lab, was unavailable for comment as of press time.)

Nulf anonymously filed grievances with the Texas Forensic Science Commission in the spring of 2009, while still employed at the lab. “I knew they weren’t following protocol,” he says. “I knew they weren’t being scientific.”
Beyond the expired chemicals and the box fan—in their report to ASCLD/LAB, the crime lab said that the fan was used only temporarily and that it faced away from areas where evidence was handled—Nulf also says that, in the year he worked for the crime lab, he was never asked to submit his own DNA for an employee database used to investigate potential contaminations. An employee DNA database is standard procedure for all crime labs.

Nulf was fired in May 2009, in part because he insisted on making a notation in the lab’s logbook that he had used an expired chemical. He was told that the notation was made “without direction from a supervisor and without sufficient documentation.” He publicly attached his name to his previous complaints in a wrongful termination suit filed against Dallas County in October of that year. Local media jumped on the suit, as it contained powerful statements that accused the crime lab of a “total lack of professionalism” and that “the same evidence used to convict murderers and rapists may be used to put them back on the street.” Nulf’s suit couldn’t go to trial because of a procedural technicality. He had failed to file his complaint with the county within seven days of his termination, as per policy. He and his lawyers filed a nonsuit, ending the litigation.

With no recourse in court, Nulf has waited two years to hear the state commission’s response to his complaints. He has amassed a pile of documents via open-records requests to shore up his case. One of those documents is a “corrective action report,” an internal memo created when problems are found in the lab. A report labeled CAR-07-007 details that “areas of the Trace Evidence Lab and office were contaminated with blood,” on or about July 16, 2007, per Dr. Timothy Sliter, the lab’s evidence section chief. The report itself, though, contains the signature of a crime lab employee, Karen Young, who didn’t work for the lab in 2007. Nulf also noticed that the template used for the report looked different than others used in that year. The report lists a resolution date of November 25, 2008. It was not, then, created contemporaneously with the contamination discovery, but 16 months later.

Nulf believes Sliter withheld information about a widespread contamination for 16 months. He says that’s the kind of information defense attorneys would have found very useful. With the prosecution, say, pointing to blood from the crime scene found on the accused’s shirt, the defense could raise the question of whether the blood might have been transferred to his client’s shirt as it was being analyzed in a contaminated lab.

When D Magazine contacted the Texas Forensic Science Commission to inquire about the status of Nu
lf’s complaint—the commission’s website still says a decision has been “abated” pending Nulf’s civil litigation, which was terminated in July 2010—a commission rep said Nulf’s complaint had been dismissed back in August 2010.

The dismissal didn’t come as a surprise to Nulf, because he’s never been notified by the commission about his case’s status. Representatives for the commission claim they did notify Nulf and that the case was dismissed on the grounds that he did not tie his complaints to a particular criminal case, as is required by the commission’s protocol. That protocol, however, wasn’t adopted until January 2010—months after Nulf had filed his original complaint.


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