Laws that ban texting while driving are ineffective at best and could be counter-productive because they encourage surreptitious behavior behind the wheel, a study funded by US auto insurers said Tuesday.

The nonprofit Highway Loss Data Institute (HLDI) said it found no reduction in auto crash claims after bans on texting while driving went into effect in four US states.

Such regulations are the law of the land in most of the country's 50 states, as well as the capital Washington, the first jurisdiction to enact such a ban.

The group said its study, which tabulated the number of collision claims immediately before and after bans on texting while driving went into effect, found a slight increase in the frequency of collision insurance claims filed from crashes in which texting played a role after the laws were enacted.

"Texting bans haven't reduced crashes at all. In a perverse twist, crashes increased in three of the four states we studied after bans were enacted," said HLDI president Adrian Lund.

"It's an indication that texting bans might even increase the risk of texting for drivers who continue to do so despite the laws."

Yet President Barack Obama's Transportation Secretary Ray LaHood criticized the report as "completely misleading" and accused the HLDI of trying to discredit government efforts to make driving safer.

"Lives are at stake, and all the reputable research we have says that tough laws, good enforcement and increased public awareness will help put a stop to the deadly epidemic of distracted driving on our roads," he said in a statement.

HLDI's findings, which examined data from various US states such as California, Louisiana, Minnesota and Washington, were presented at an annual meeting of the Governors Highway Safety Association.

Lund said crashes increased after the bans because drivers engaged in even riskier behavior by covertly texting behind the wheel.

"Clearly, drivers did respond to the bans somehow, and what they might have been doing was moving their phones down and out of sight when they texted, in recognition that what they were doing was illegal," he said in a statement.

"This could exacerbate the risk of texting by taking drivers' eyes further from the road and for a longer time."

The findings "call into question the way policymakers are trying to address the problem of distracted driving," Lund added.

He noted that in earlier research, his group found that banning handheld cellphones also failed to reduce car crashes.

But LaHood stressed that crashes related to distracted driving killed nearly 5,500 people in 2009 (down from 5,870 in 2008) and injured nearly half a million more.

Last week, the transportation chief called for warning labels on mobile phones to remind Americans that the popular devices can become deadly distractions if used while driving.

Search for used cars