You can't see it, but it's there, and it has been for years: GPS signals from police cars zooming around our city.
Houston Police Department has them; the Harris County Sheriff's Office, too.
Harris County Precinct 4 Constable Ron Hickman is the newest lawman to have his patrol cars outfitted with GPS devices.
"The cars report their GPS every 3-4 seconds," Hickman said.
They help law enforcement agencies figure out where their units are -- and where they aren't going. And we've used them, too, to show you where the police protection you're paying for is being deployed. Years ago we mapped HPD GPS information. A union leader at the time said it exposed how short-staffed HPD was.
"There aren't enough and obviously your GPS will make someone think that," Hans Marticiuc told us in November 2007.
And just last year, 13 Undercover revealed HCSO deputies rarely patrolling neighborhoods paying for extra security.
"This is ridiculous as much as we pay for taxes. That's not right," Sadie Thomas told us in February 2012
The sheriff's office blamed it on staff shortages. Even Constable Hickman said the GPS data was revealing.
"It's unfortunate to see that sort of absence of coverage, if you will," Hickman told us in February 2012.
But now that Hickman has it in his patrol cars, he says it's too dangerous to reveal to the public.
"Let's don't tell the criminals what the routine patrol patterns are," he said.
And he went to his state lawmaker to keep police GPS databases secret.
"When the bill was brought to my attention by the largest constable's office in the nation, I thought it looked like good legislation," said State Rep. Allen Fletcher (R-Cypress).
Fletcher is shepherding a bill through the state house that would allow law enforcement agencies to hold on to GPS information forever, without releasing the data to you.
Not to save them embarrassment, no. They say to keep the crooks from requesting it, tracking it and picking targets to victimize.
"You really think criminals would do that?" we asked.
"I do," Hickman replied. "Knowing what I know about high-tech crime, I do."
"Has it ever happened?" we asked.
"I don't know," Hickman said.
As a compromise, Hickman would be willing to give us a printed map of his data, just not the data itself. But he can't do that yet. It takes considerable computing power to map this stuff.
He and Rep. Fletcher suggest the law is designed to keep crooks from doing what he can't.
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