CHAPEL HILL - Chapel Hill’s cell-phone debate got put on hold Monday night when a proposed ban on calls while driving fell two votes short.

To pass on a first reading, the ban needed six votes. The council deadlocked 4-4, with member Ed Harrison absent because he was representing the town at a regional transit meeting.

The issue will come back for a second reading March 26, when it will only need five votes.

The town has discussed the issue for two years. Another yes vote for a full ban next time could make Chapel Hill the first in the nation to enact such a ban, according to the town attorney. Evanston, Ill., which has had a local ban on hand-held calls, is considering adding hands-free calls to its ban.

Chapel Hill’s proposal calls for banning either hand-held cell phone calls only or both hand-held and hands-free cell-phone calls while driving in town limits.

It would make such calls a secondary offense, punishable by a $25 fine, when police stop someone for another violation such as speeding. It would make exceptions for emergencies and calls with family members consistent with the state’s cell phone ban for drivers under 18.

Monday’s opponents cited a state assistant attorney general’s opinion that Mayor Mark Kleinschmidt, who voted against the measure, called “reasonable” and “rationally laid out.”

When asked last year whether the town had the statutory authority to regulate cell phone use while driving in town limits, Assistant Attorney General Jess Mekeel was unequivocal.

“No,” he wrote.

In a Nov. 2, letter, Mekeel said the town may not regulate activity in a field where the state intends to provide “a complete and integrated regulatory scheme.” He cited the state’s existing ban on cell phone use by drivers under 18 and school bus drivers, as well ban on anyone reading email or texting while driving.

The benefit of having uniform rules across municipalities also weighs against the town’s enacting a local ban, he said.

But other legal experts, including Town Attorney Ralph Karpinos disagreed. In a memo, Karpinos said the courts would have to decide if the town passed a ban and someone challenged it.

That would most likely come from someone getting cited, said Shea Denning, an associate professor of public law and government at UNC-Chapel Hill and a former assistant federal public defender.

In a post of the School of Government blog, Denning said it’s too close to call.

The state already allows municipalities to regulate traffic activities such as speed limits, she noted. The question would be whether existing statewide cell phone rules are part of that “complete” regulatory scheme that would preempt a local ban.

Town Council member Penny Rich said Evanston’s experience shows the ban is a good idea.

The home of Northwestern University has a population of 77,000 residents compared to Chapel Hill’s 58,000, she said. In the two years since it enacted the hands-held ban, accidents have decreased 17.6 percent, she said.

Evanston fines people $50 per offense, and up to $200 if a person using a cell phone gets into an accident.

According to the city of Evanston, since the hands-held ban began in March 2010, there have been 2,979 violations and total fines of $149,805, the Pioneer Press reported last week. Of that, $124,685, or 83 percent, has been collected.

“People are not fighting the tickets,” Rich said. “People know when they’re coming from Chicago to hang up the phone.”

But other council members were not convinced.

Matt Czajkowski wanted to know how much signs explaining the local ban would cost and how much money the town was willing to spend to defend its legality.

“At the end of the day we’re about to pass an ordinance the attorney general has told us we don’t have the authority to enforce,” he said. “The last thing we want is to have this challenged and lose.”