Drivers can be stopped for using a cellphone and cited even if they are not violating any other law. The base fine for the first offense is $20, and it's $50 for subsequent convictions.
A separate law, which also takes effect today, prohibits drivers younger than 18 from using any kind of mobile device while driving. They can't even use devices to text message -- something adults are not precluded from doing by the law.
On Monday, last-minute shoppers were busy buying hand-free devices. A steady stream of customers trolled Aisle 76B at a Fry's electronics store in Industry on Monday afternoon, where there was some grumbling about having to fork over anywhere from $20 to $100 for Bluetooth earpieces. Half the aisle was already picked bare.
"I have no clue which one to buy," said Barbara Guerrero, a 33-year-old Mary Kay saleswoman running errands with her two daughters. "I bought one before, but it wasn't compatible with my phone. I can't afford to miss a call in the car, because my cellphone is my work number."
In Pasadena on Monday morning, Albert Hernandez walked out of a BestBuy carrying a $72 Bluetooth earpiece.
"I already bought one for myself, but I figured I should get one for my wife before it's too late," said Hernandez, 28, of South Los Angeles. "I haven't even taken my one out of the box."
He said he expected enforcement to be mixed.
"I have tinted windows, so I don't know how they'll see as well," he said.
Matthew Roth, a historian for the Automobile Club of Southern California, said it often takes time for drivers to change their behavior. He cited the long push in the 1920s for motorists to come to a complete stop at major intersections (rather than the rolling "California stop") and the decades-long campaign to stigmatize drunk driving.
Often, he said, it's societal pressure more than tickets that ultimately leads to change.
"If people adopt a behavior for their own reasons, internally, I think then they will behave that way whether there's a radar gun or a CHP officer lurking nearby," Roth said.
Sgt. Edmundo Hummel of the Los Angeles County Sheriff's Department said deputies were "not going to have a zero-tolerance" policy on the driving-while-on-the-cellphone law, as they would with fireworks or gun violations.
But he and other officials added that there was also nothing stopping authorities from enforcing it aggressively.
