MONTGOMERY COUNTY, Texas – A former deputy with the Montgomery County Sheriff’s Office doctored, forged and faked speeding tickets to appear more productive, according to internal documents obtained by Channel 2 Investigates.

Senior Sgt. David Wallace resigned before the Internal Affairs investigation concluded, but a district court judge found Wallace guilty of tampering with a government document.

During his career with the Sheriff’s Office, Wallace wrote thousands of traffic enforcement tickets and collected thousands of dollars in overtime doing it.

In 2008, Wallace received a commendation for his proficiency in writing speeding tickets.

Wallace was a member of team that conducts traffic enforcement as part of a federal grant to curb traffic violations. It appears his overtime was largely paid with federal tax dollars, although the Sheriff’s Office is required to match funds to support the program.

“I didn’t fabricate tickets,” Wallace said during a short interview with KPRC 2 News Joel Eisenbaum.

[READ: Selection of tickets deemed fabricated by the Montgomery County Sheriff's Office Internal Affairs]

In a longer, taped audio interview with a Montgomery County district attorney investigator and Texas Ranger, Wallace admitted to falsifying at least one ticket, a ticket written to his girlfriend, someone he never pulled over.

“I mean, I just feel like I needed to get those numbers, that’s all, that’s all,” Wallace said.

During the 30-minute conversation Wallace makes several references to a ticket quota, one he believed he was required to meet to keep his lucrative overtime “extra job.”

“I would be more than happy to write the warning, that would be wonderful, wonderful, but the requirements, they say the Texas Department of Transportation wants three citations an hour, and the county says -- or we say -- we want four an hour,” Wallace said during his official interview with investigators.

Traffic enforcement quotas are prohibited by Texas law, and in extreme cases can lead to a sheriff being removed from office.

The Sheriff’s Office maintains, resolutely, that it does not ask deputies working traffic enforcement to meet any sort of quota.

“No, there is no quota at the Sheriff’s Office,” Lt. Brady Fitzgerald said.

An internal affairs investigation found that over a two-week period, at least 19 tickets were changed from warnings to citations without the drivers' knowledge.

In some of those cases, Wallace forged the name of the driver and never issued the driver any paperwork at all.

“He wanted to make it look like he had issued a citation, kind of pad his statistics,” Assistant District Attorney Joel Daniels said.

Daniels, the chief of the public integrity section of the Montgomery County District Attorney’s Office, prosecuted Wallace.

Wallace had a prolific ticket-writing career with the Sheriff’s Office, but investigators appeared to look specifically at a two-week period during the summer of 2015.

Importantly, neither investigators with the Sheriff’s Office nor investigators with the District Attorney’s Office found any evidence that Wallace forwarded the faked tickets to the courts, so it does not appear drivers’ records were dinged, at least during the examined period.

Wallace signed a document which prohibits from applying for peace officer certification in the state of Texas.