DWI expert yanked off cases after questions about previous blood tests

One of the state's leading DWI analysts has been removed from case work after conflicting testimony surrounding a lab error.

Collin, Dallas, Denton and Rockwall counties will no longer use expert Christopher Youngkin, which likely means retesting of hundreds and perhaps thousands of blood samples he's previously worked on.

DPS removed Youngkin from case work pending administrative decisions, a DPS spokesman said Friday.

Local attorneys are now searching to see if any of their cases are affected.

"We will be spending weeks pulling out all these old cases and going through each one to see which ones have his name on them,” said defense attorney Deandra Grant.

Youngkin is a DPS forensic analyst under scrutiny for not divulging a lab error in 2013. In that incident, Youngkin admits he switched blood tubes resulting in wrong blood alcohol reports.

The concern about his testimony in cases since then led to a deposition on Monday.

A DPS Quality Action Plan document shows Youngkin was in charge of investigating his own 2013 error, calling it an isolated incident. But since 2013, as one of the state's leading expert witnesses for DWI cases in seven counties, he never told any of the district attorney’s offices about it. 

"We gotta pull out every case where he was the analyst,” Grant said.

The Texas Forensic Science Commission, created in Sept. 2015, is now responsible for accrediting DPS labs and investigating claims of professional neglect or misconduct.

The commission's general council Lynn Garcia said in a statement the investigation procedures have changed.

"The quality assurance process at DPS and many other labs both in and outside of Texas has evolved since this QAP - QUALITY ACTION  PLAN - was issued.  While the individual directly involved ... still participates in the root cause analysis, he or she is not the primary party responsible for completing the QAP."