INDIANAPOLIS — State officials and advocates for a newly signed law that bans motorists younger than 18 from using cell phones are drafting plans to make sure teenagers — and their parents — know about the looming ban.

The bill signed last week by Gov. Mitch Daniels bans people younger than 18 from using cell phones and other telecommunications devices while driving.

When the law’s provisions take effect July 1, it will be illegal for motorists under age 18 to chat, text, or use a phone to make videos of friends in a car.

Rep. Peggy Welch, D-Bloomington, said the news about the new law is already spreading to the state’s teens through some of the same electronic communications the law targets.

“These kids Facebook, they Twitter, they text. The word is going to get out real fast, but I think the advocates for the bill are going to be interested in some additional communications,” said Welch, the bill’s author.

The ban on cell phone use is considered a primary enforcement law, which means police can pull over drivers if they believe they are younger than 18 and using a cell phone or other telecommunications device.

But Indiana State Police spokesman Dave Bursten said police aren’t likely to search for new drivers using the phone because troopers “don’t have the luxury of that much time.”

A trooper who is between other calls or already working traffic patrol may make a stop if a driver looks especially young and is chatting on a phone, Bursten said.

“But more realistically, it will happen when they’ve been stopped for another violation, like running through a red light or excessive speed,” he said. “We see a lot of things in the process of pulling people over — people grabbing their seat belt or putting a phone down.”

Welch said she expects police to be somewhat lenient when the law first goes into effect. She said officers might give teens warnings. That’s what happened when the state began implementing a law requiring booster seats for older children.

“This is for education and safety and not to whack people and punish people,” Welch said

A Bureau of Motor Vehicles staff task force had its first meeting last week to start developing a plan for implementing the bill, which also imposes some new restrictions on the hours and passengers for new teen drivers.

In addition, the law will force teens to be a few months older to get their licenses, although that change won’t go into effect until July 1, 2010.

The AAA Hoosier Motor Club, one of the bill’s biggest advocates, already has a communications strategy, said Sherry Deane, the group’s public affairs director. AAA is creating posters and handouts for license branches and high schools.

The AAA already has a one-page handout with a side-by-side comparison of the old law and the new one, and it’s sending the law to middle and high schools with a request that the information go on the school Web sites and in school newspapers.