Montgomery County DWI cases may be botched


On this no-refusal Memorial Day weekend, drivers in Montgomery County will be asked to submit to a Breathalyzer test. But a group of lawyers who represent clients in this county say the results of those tests may be unreliable.

If you're stopped on suspicion of DWI in Montgomery County, a Breathalyzer was likely used to test your sobriety. Defense attorney Mark Thiessen says that's a problem.

"If he was cutting corners here, who's to say he wasn't cutting corners elsewhere?" Thiessen said.

DPS technical supervisor Glenn Merkord's certification was suspended for a month after he failed to perform proper maintenance on a machine and certified three officers to perform blood alcohol testing who had failed a written test.

We reached out Merkord, but he declined to comment.

But the Montgomery County DA's office sent a memo informing defense attorneys that "Inxoxilyzer instruments in Montgomery County did not receive acetone checks when the devices were taken out of service and transferred to another location...contrary to DPS guidelines."

Thiessen is concerned that a client's case may be invalid.

"Acetone is an interferent. People with diabetes can blow interference. People on high-protein diets can blow interference," Thiessen said.

He says as many as 1,200 could have been compromised. Montgomery County prosecutor Warren Diepraam disagrees.

"I would say it's 10. Probably as few as four individualy cases that may possibly be impacted by this concern," Diepraam said.

He also disputes the impact of the error.

"Basically, we're talking about a thousandth of a percent that it could have affected the Intoxilyzer readings," Diepraam said.

But if it's your DWI case, Thiessen says close is not good enough.

"I think it was gross negligence," Thiessen said.

DPS says it's also looking into two cases in Trinity County and another in San Jacinto County.

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