Jack Gold, a wireless analyst for J. Gold Associates in Northboro, Mass, predicted that CTIA's position "won't hold up much longer because it goes against the tide and makes no sense. It's insane what people do when they drive and talk on their phones. I'd venture to say a majority of states will put measures on their book in a few years."

Many companies in recent years have recommended to their workers that they use hands-free devices while talking on a cell phone and driving, regardless of the law. But some IT managers doubt the advice is being followed by all workers.

"I think it's pretty widespread that people ignore that company advice," said Geoff Caras, vice president of system infrastructure for Shop.com in Monterey, Calif. He was offering his own opinion, not the views of his company.

Caras said nobody at his company has told him to use a hands-free device, and argued that many companies are probably only issuing the advice to reduce their liability and make their insurers happy. As for the California law, Caras said, "I'm on the fence about whether a law is needed. I think we all have seen a guy driving slow in the fast lane, only to pass him and see he's holding a cell phone to his ear. But on the other hand, I've personally called 911 when I saw an accident and held the phone to do it."

Caras said for truck drivers in service fleets and others who drive all the time, a hands-free technology, whether for voice or data, is "absolutely crucial" and something he'd like to see universally.