Of course he wouldn't think she's guilty of any wrong doing. A two-minute Google search brought a few things up.
A) he was one of the investigators for the killing of Chris Kyle of American Sniper fame
B) he killed a passenger in a truck driving almost twice the posted speed limit of 45MPH.
From
here:
A fatal traffic wreck involving Texas Ranger David Armstrong of Dallas is a good example of the double standards inside DPS. On February 2, 2017, Ranger Armstrong was returning from a special operations shift on the Mexican border when he crashed his DPS vehicle into a pickup truck, ejecting both the driver and the passenger. After several weeks, a DPS Highway Patrol accident reconstruction team was able to recover the vehicle’s computer to confirm his speed at the time of the crash. He was driving 84 miles per hour on Highway 281 in Premont, where the posted speed limit was 45 miles per hour. Ranger Armstrong fractured his hip, and his DPS vehicle burned down to the metal. The passenger of the other vehicle, 30-year-old JD Kristopher Trevino of Premont, died of his injuries five days after the wreck. Even though the accident occurred in Premont city limits, and even though accidents in municipalities are normally investigated by city police, DPS handled the investigation so it could cover up what happened. Among other things, Ranger Armstrong was violating a DPS safety rule at the time of the accident. That rule mandates that officers working on the border take a six-hour rest period before driving home, and the rule had been in effect for more than a year at the time of the accident. Ranger Armstrong had repeatedly violated the rule – a fact known to his supervisors – and he was violating it again when he was driving through Premont at 10:15 p.m. Although most drivers would have been charged with manslaughter, criminally negligent homicide, or at least reckless driving, Ranger Armstrong was never charged with anything, nor was he disciplined. Instead, the entire incident was covered up by senior DPS commanders, and Ranger Armstrong is now leading a high-profile investigation into a police shooting in Dallas.