By Tom Benning

Texting or talking on the phone while driving is demonstrably dangerous _ a fact that's backed up by reams of research. There's no denying either that cellphone use while driving can cause accidents _ Austin, even with flaws in the data, saw 70 of those wrecks in 2014 alone.

But banning the practice doesn't necessarily reduce accidents.

A Dallas Morning News analysis of the imperfect crash data in 12 Texas cities with cellphone rules found no consistent reduction in distracted driving wrecks after cities enacted bans. And that follows equally mixed reviews found by scientific studies on statewide bans on texting or handheld cellphone use while driving in other states.

"It's not clear the bans in place have had the desired effect," said Anne McCartt, senior vice president for research at the Insurance Institute for Highway Safety. "There are a lot of issues related to enforcement, data and other things, but that's the bottom line."

Texas is one of just six states in the U.S. to not have at least a statewide ban on texting behind the wheel. (Texas bans younger drivers from any cellphone use while driving, along with barring all drivers from texting or handheld cellphone use in school zones.)

State Rep. Tom Craddick, R-Midland, has pushed hard for three sessions to pass such a statewide texting prohibition. Relatives of those killed in distracted-driving crashes have given heart-wrenching testimony. But concerns over enforcement and personal privacy have won the day in the Capitol.

Around 40 Texas cities have stepped forward to ban texting while driving, including five in North Texas: Arlington, Denton, Farmers Branch, Grand Prairie and Rowlett.

Some cities, such as Austin, have gone further by barring motorists from using any hand-held electronic devices.

Austin moved to its "hands-free" ordinance in January, after having a texting ban since 2009. The city moved to the broader rules in part because they are more enforceable: a chatterbox holding a phone up to an ear is easier to see than someone texting in their lap.

The new ordinance resulted in 551 tickets in February alone. In all of last year, Austin police wrote 688 citations for the texting ban.

On a recent morning, Borne, the police officer, saw three drivers using their cellphones over a couple of hours on patrol. Though he said that seemed to be an abnormally low number, he said he sensed that drivers are starting to get the message and stay off their devices.

But is the ordinance making the roads safer?

Borne acknowledged that it's difficult to know for sure. Sitting at a busy intersection, though, he pointed to the stakes. Not long ago at that spot, he saw a woman run a red light while looking at her phone.

Engrossed in a text message, she never saw the light change.

"That guy with the bike there," he said, pointing to a man walking his bike across the intersection's crosswalk. "What if he had been there that day?"

To see what impact these ordinances might be having, The News analyzed Texas Department of Transportation crash data for a dozen cities that have passed them. The data focused on wrecks in which cellphone use or distraction was a contributing factor.

But the statistics, which rely mainly on driver accounts from the scene of a crash, raised more questions than they answered.

Several cities saw the crash rate for cellphone-involved wrecks drop after implementing either a texting or a hands-free ordinance. But many of those same cities saw distracted driving crashes, which include the cellphone incidents, actually increase.

Did the ordinance actually reduce cellphone use? Or did it just make drivers even more leery to admit that they had been using their phone? Or did the elimination of one distraction behind the wheel simply lead to others?

Then some cities saw crash rates increase after implementing new rules. Some saw those rates go up and then go down. And some indeed saw an apparent drop in both crash categories.

But there are many variables at play.

In Corpus Christi, for instance, a police spokesman explained that his city's precipitous drop in those crash rates was likely just the result of the fact that the department no longer fills out crash reports on wrecks that don't cause at least serious injury.

Despite those challenges, some argue that such volatility adds to the need for a statewide ban on texting behind the wheel. That would reduce confusion drivers might face in knowing which cities have ordinances and which ones don't.

(c)2015 The Dallas Morning News