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Drivers have the option of using a headset, a Bluetooth ear piece, or a mounted cradle. They can also place their phone on speakerphone mode in their lap or seat.
There's been a lot of criticism about the new law. Some experts say the act of holding the phone isn't necessarily the danger. They say the problem are drivers focusing on the conversation instead of on the road.
Effective or not, the law kicks in at midnight.
"This will mark new protections for drivers, not only drivers but their passengers and anybody who's on the road," said state Senator Gloria Romero, D-East L.A. "So at midnight tonight, the stroke of midnight, the new law goes into effect."
"Irresponsible cell phone luxury is pushing your luck," said state Senator Ron Calderon, D-Montebello. "You simply can't drive safely. It's been proven."
Any driver seen holding a cell phone to their ear is subject to a $20 fine for a first offense and a $50 fine for subsequent tickets. When all fees and penalty assessments are added to the fine, the first ticket will actually cost $76 and subsequent tickets will cost $190.