We will follow the money trail all week long, using the county's own computers to uncover the evidence -- even as the constable tries to stop us from seeing all the records.
Fiestas Patrias -- Saturday's parade honored Mexican holidays and it has deep roots in Houston. And there's Victor Trevino, waving to the crowd.
For more than 20 years, the constable has been the popular face of law enforcement on Houston's mostly Hispanic east side.
"I grew up in this area. I still live in this area and I've seen the progress here," Trevino said.
And why wouldn't he be popular? He arranges birthday songs for senior citizens, sponsors Little League teams. He's even got the guy who plays Pancho Claus at Christmas on his payroll.
But wait till you see what we caught his captain saying about him on hidden camera.
"I'm stepping down, because I know something ain't right," his captain said.
Wait until you the see the financial records 13 Undercover has uncovered -- charity money unaccounted for.
"This is all done in cash," we told KTRK Legal Analyst Joel Androphy.
"Which is even more suspect," Androphy replied.
Records documenting the possible misuse of county equipment and deputies.
"These are Harris County tax dollars at stake, and to me, this money is sacred," Anna Nunez said.
Because Anna Nunez used to work for the county tax office before Victor Trevino hired her last winter. It didn't take long for her to say, 'wait a minute.'
"He was abusing public trust, abusing public dollars," she said.
There's something very private this single mom is allowing us to share with you. She says the constable knows.
"I have a brain tumor, and it's... Sorry," Nunez said.
Anna Nunez was laid off in June. The constable calls her a budget casualty, but she's the only employee laid off in Precinct 6 this year, and it was just one day after the constable found out we were investigating.
"You think you were fired because they thought you were a snitch?" we asked Nunez.
"Absolutely, absolutely," she replied.
"She doesn't know me. She doesn't know me because that's not what Victor Trevino has ever been about or is about or ever will be," Trevino said.
"So, not only did he mess with my financial livelihood, that's one thing, but to mess with my life as a mother was unforgivable," Nunez said.
Anna did not start our investigation. Anonymous letters from Precinct 6 begged for our help. But Anna helped handle the money in this county building and she kept great records. She's now helping us to help the deputies.
"They all feared for their job," Nunez said. "Many of them said, 'This is the way it is. What can we do? There's nothing we can do to change and it is what it is,'" Nunez said.
"The reason I'm here is because your deputies had to come to us to complain about the way you and your command staff were treating them," we told Trevino.
"And I believe in that right," Trevino replied.
"The evidence is overwhelming that this practice was going on for years," we said.
"What you have is information. You have information that you've been given," Trevino said.
But you'll see the evidence in black and white. If you worked at Precinct 6, you were expected to pay up for Trevino's charity, for his campaign.
"What made me upset was seeing officers having to come in on their own time, pulling out cash, their own personal checks," Nunez said.
The constable's defense? He's become lax.
"To make anyone feel compelled or forced to volunteer or to participate in a charity is not acceptable," Trevino said.
Even commanders complained in emails about the constant drumbeat for money.
"He is killing us," one email read.
Another top commander wrote, "Do I need to remind you who you work for!!!"
"No one has been terminated because they said, 'I don't want to participate in this,'" Trevino said.
"Well, you think they're stupid?" we asked. "You're going to be the deputy that says to your supervisor, 'I'm not going to give him any money.'"
"No, we've had that," Trevino responded.
"You think it was a shakedown?" we asked Nunez.
"Oh, absolutely," she said.
On Tuesday, the damaging emails. We'll focus on the charity that's been operating out of Trevino's office. Why is he hiding bank records from us, and wait until you see what we caught on hidden camera -- Tuesday night at 10.