Fort Worth

Tarrant County DA’s office questions credibility of lab tech

The lab technician in question processed blood samples from DWI cases in Tarrant County.
The lab technician in question processed blood samples from DWI cases in Tarrant County. Star-Telegram archives

Tarrant County prosecutors have notified dozens of defense attorneys regarding the credibility of a lab technician who testified for the state in numerous DWI cases.

The Tarrant County district attorney’s office also said that the technician, Elizabeth Feller, has been barred from further testimony because she failed to disclose that she had been reprimanded for mishandling blood samples at a previous job.

Prosecutors sent out more than 180 Brady notices in mid-May that dealt with the misdemeanor DWI cases, and several others involving felonies.

This batch of disclosures is not related to the more than 4,000 Brady notices the DA’s office has sent to criminal defense attorneys after learning that the credibility of 16 officers and three breathalyzer operators had previously been brought into question, officials said. The Star-Telegram reported Sunday that District Attorney Sharen Wilson launched an exhaustive review after 22 3-inch binders, which contained more than 6,000 handwritten notes entered by past prosecutors, were found in misdemeanor offices and brought to her attention after she took office in January.

In 19 of the notes, the prosecutors accused the officer or breathalyzer operator of lying, though not always on the witness stand, Wilson has said.

Under Brady disclosure, named for the U.S. Supreme Court ruling in Brady v. Maryland, prosecutors must make available to the defense any exculpatory or impeaching information and evidence that is material to the guilt, innocence or punishment of a defendant.

Feller worked for the Bedford-based Integrated Forensics Laboratories, which is contracted to test blood samples from Tarrant County agencies taken from Oct. 1, 2014, through Sept. 30, 2015, during special DWI holiday enforcement efforts.

Feller, an IFL lab analyst, told an employee with the Tarrant County DA’s office that before working with IFL, she had been terminated by a previous employer, according to an email from Misdemeanor Chief Mike Mitchell.

Feller stated that the employer never had any other issues with her work, Mitchell said. But the district attorney’s office later discovered that Feller had received a written reprimand — which she did not disclose — that was not related to her firing, Mitchell said.

“Based upon her failure to accurately state the facts in regard to this issue in the disclosure she previously provided to the Criminal District Attorney’s Office, ... Brady notices were subsequently sent this Spring stating that Ms. Feller will no longer be sponsored as a witness on behalf of the State of Texas in cases prosecuted by the Tarrant County CDA’s Office,” Mitchell said.

According to material attached to the Brady notices, Feller was fired on Feb. 2, 2013, from Cellmark Forensics in Dallas because she mishandled a group of biological samples, and then neglected to follow proper procedures to correct the error and notify her superiors. As a result of the mistake, the sample results were significantly altered, the attachment states.

“I have other employment right now and I can make no further comment on this issue,” Feller said Wednesday.

This article contains information from Star-Telegram archives.

Mitch Mitchell, 817-390-7752

Twitter: @mitchmitchel3

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