DPS Invalidates All of Scientist's Breath Tests

She's accused of faking records, so people found guilty with the evidence can challenge it.

By Peggy O'Hare

DPS requires technical supervisors such as Deetrice Wallace to have a bachelor's degree in a scientific field with at least 18 hours of chemistry. They are also required to complete a 40-hour breath alcohol testing operator class, a technical supervisor course in Indiana and a factory maintenance and repair course with CMI Inc., the Kentucky-based manufacturer of the Intoxilyzer. They must pass a certification exam.

The supervisors are subjected to quality assurance tests twice a year and must undergo annual inspections, during which their records are examined and their skills are evaluated by a supervising forensic scientist.

The arrest of a forensic scientist accused of falsifying records has raised questions about the state's alcohol breath testing program and the validity of test results used against drunken-driving suspects in court.

Houston resident Deetrice Henderson Wallace was one of 55 technical supervisors across the state certified by the Texas Department of Public Safety to inspect Intoxilyzer machines and download defendants' breath test results for shipment to DPS headquarters in Austin.

Her arrest last week jeopardized an estimated 2,600 drunken-driving cases filed in the Houston area since 2003, state officials said.

DPS officials, however, have invalidated all breath tests ever recorded by Intoxilyzers under Wallace's supervision, said Mack Cowan, the DPS scientific director of the Texas Breath Alcohol Testing Program.

"We can't pinpoint a date where she became unethical," Cowan said. "So that's the way we decided to handle it."

As a result, breath test results generated by any of Wallace's Intoxilyzers cannot be used as evidence against defendants still facing drunken driving charges, Cowan said.

People found guilty after submitting to such tests may challenge their convictions, he said.

Wallace and other technical supervisors play a critical role in the state's effort to crack down on intoxicated drivers. They calibrate and ensure the accuracy of the Intoxilyzers that collect breath samples from drivers as well as repair the equipment, train and supervise the police officers who give the breath tests, and testify in court.

Some of the supervisors work for DPS or city or county government agencies. Others, such as Wallace, are independent contractors.

Critics say state oversight of the supervisors' work is lacking, but Cowan said he has full confidence in the program and described Wallace's alleged actions as an anomaly.

"For us to have this happen is very embarrassing," Cowan said.

Friendswood Police Chief Bob Wieners — whose police department paid $8,000 a year for Wallace's services — said he questions whether DPS' oversight is adequate.

"Incidents like this undermine the special trust and confidence the public should have that the procedures are overseen the way they should be," Wieners said.

Wallace, 45, who also taught robotics at Sharpstown High School and was honored as the 2006 Teacher of the Year by the Education Foundation of Harris County, declined to comment. After her arrest, she was reassigned to off-campus duties.

She is charged with felony tampering with a governmental record and is out of jail on $2,000 bail.

"It's my desire Ms. Wallace be accorded the presumption of innocence as the process runs its course," her attorney, George "Mac" Secrest, said Friday, declining further comment.

Wallace had participated in the state's alcohol breath testing program since 1994 and had private contracts with eight police departments — Friendswood, Pearland, League City, Webster, Seabrook, Galveston, Clute and South Houston — at the time of her arrest. DPS suspended her certification Oct. 23 after an internal audit found she falsely reported inspecting the Intoxilyzer at the South Houston Police Department.

Wallace admitted to investigators that she had falsified inspection records for both the South Houston and Clute police department Intoxilyzers, a criminal complaint shows.

Some of the police departments owned the Intoxilyzers under Wallace's supervision, while others borrowed or leased the devices from her, Cowan said. All the machines have been seized and are now at DPS headquarters in Austin.

DPS does not keep records of how much money technical supervisors earn. But two other supervisors who were self-employed like Wallace estimated their incomes at $50,000 to $100,000 a year.

"It's considered really poor pay for this kind of work, frankly. For a scientist of this caliber, it's not very high," said chemist Allen McDougall, who owns Bexar Breath Testing in San Antonio and supervises every Intoxilyzer in Bexar County, as well as one in Schertz in nearby Guadalupe County.

"I don't know what all the independents are making, because some of them only work part-time," McDougall said.

Houston defense attorney Troy McKinney, who has been critical of the Intoxilyzers' scientific integrity, said the state's inspections are "perfunctory."

"I think Dee Wallace is just the tip of this iceberg," McKinney said.

But Cowan said that while there could always be more oversight, he is satisfied with efforts to watch over the technical supervisors' work.

DPS has changed its procedures to compare more of the supervisors' computer records with hard-copy printouts from the Intoxilyzer, he said.

"We have checked every other technical supervisor in the state to see if any red flags were brought up. There were not," Cowan said.