Toll road operators in North Texas are ignoring state law by imposing arbitrary speed limits that are set far below the safest level suggested by engineering surveys. A WFAA-TV investigation discovered that the North Texas Tollway Authority set speed limits on portions of the Dallas North Tollway and all of the Bush Turnpike without performing the scientific studies required by state and federal law.

"Statistics show that 85 percent of the people drive at a prudent and reasonable speed," Kelly Selman, TxDOT director of transportation, told WFAA. "If you set a speed limit lower than that, you're actually punishing prudent and reasonable drivers."

A section of the Dallas North Tollway running from downtown to I-635 is posted at 55 MPH while the vast majority traffic was measured to flow at a safe and reasonable 72 MPH. That means police could write 590 speeding tickets to toll road users every minute for driving 17 MPH over the limit, based on the amount of traffic on the toll road. The tollway generated $191 million in tolls last year.

A North Texas Tollway Authority spokesman denied the road was designed to be a speed trap. Currently, Texas allows the highest legal speed limit in the country at 80 MPH.