DPS forensic analyst questioned about lab sample mistakes

A state crime analyst who testified in thousands of DWI cases was questioned under oath about a mistake he made with lab samples more than three years ago.

Several criminal defense attorneys have called into question Christopher Youngkin's testimony, saying he gave conflicting statements about his mistake and raising concern about his credibility.

The deposition had nothing to do with any allegations of prosecutorial misconduct but rather the questions surrounding the on-going testimony of one of the state’s leading witnesses in DWI cases. His testimony was so troubling, seven Collin County judges ordered the deposition, and representatives from several county district attorney’s offices were present.  

Youngkin is the DPS forensic analyst at the heart of hundreds of DWI cases in multiple counties that have been called into questions based on his conflicting testimony about a lab error more than three years ago.

"You knew that from May 16, 2013 and all of 2013. Correct?” Defense Attorney Troy Burleson asked Youngkin.

“Correct,” he replied.

"You knew it all of 2014. Correct?” Burleson asked.

"I did,” Youngkin replied.

"You knew it all of 2015?” Burleson asked.

"Yes, sir,” Youngkin replied.

“And all of 2016?” Burleson asked.

"To this point and time, yes sir,” Youngkin replied.

In May of 2013, court records show Youngkin switched blood samples that resulted in a sober person being wrongly identified as having a blood alcohol content nearly twice the legal limit. It came to light because the Anna Police Department questioned the results.

In a DPS document called a Quality Action Plan, Youngkin is listed as the investigator. He described it as an "isolated incident" and admits "that the tubes were switched before the sampling of the evidence, thereby resulting in the wrong results being reported."

"Who did you give official notification to at the district attorney's office of let’s just say the quality action plan? Who did you give that to?” Burleson asked.

"I didn't provide it to anyone,” Youngkin replied. “It was not my responsibility."

Attorney Hunter Biederman was present for the deposition. He represents several clients in DWI cases where Youngkin gave expert testimony.

"He never turned this information over to anybody so none of our clients and no one of anybody's clients in 10-15 thousand cases ever got a chance to utilize this information,” Biderman said. “If we can't trust him to disclose that, how do we know there haven't been other mistakes as well since then?"

DPS would not comment on Youngkin's deposition because of pending DWI cases and would not talk about any reviews of his performance.

During the deposition, district attorney representatives from Dallas, Denton and Collin County tried to get an explanation for why Youngkin never voluntarily disclosed his error, despite continuing to testify.

"So not only did you not tell any tell the DA's office, you decided upon yourself that it was not required of you to tell the DA's office. Is that correct?” Burleson asked Younkin.

"My understanding, that's correct,” he replied.

Collin County Assistant DA Bill Wirskye followed up.

"No one ever picked up the phone, told us about this,” Wirskye said. “No one at the Collin County DA's office was ever provided a copy of this Quality Action Plan. Is that your understanding as well?"

"It's certainly possible that someone in your office has received it at some point and time,” Youngkin replied.

"I'm talking about then,” Wirskey said.

"Correct,” Youngkin said.

One prosecutor said he's confident the blood test results in the pending DWI cases are accurate. He said it’s the "credibility" of a key state witness that concerns him and other prosecutors.

Seven surrounding counties have DWI cases in which Youngkin has testified. It is not clear if district attorneys in all of those counties will continue to use him as an expert witness, but the video deposition will likely be used as evidence by defense attorneys in both pending and possibly even previous cases.                    

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