Minnesota has become the first state in the nation to require smartphones to carry a so-called kill switch that will disable the devices remotely if they are lost or stolen.

"This law will help combat the growing number of violent cellphone thefts in Minnesota," said Gov. Mark Dayton as he signed the bill Wednesday.

The University of Minnesota, in particular, has experienced a rash of such thefts, with students being targeted for their smartphones and tablets. Officials say that up to 62 percent of on-campus robberies now are cellphone related.

The legislation requires that by July 1, 2015, any new smartphone sold or purchased in Minnesota must be equipped a "kill switch" or be capable of downloading such an anti-theft app at no cost. The technology allows smartphone or tablet owners to remotely disable their devices. The law also prohibits retailers from paying cash for used devices, limiting payment to mailed check or electronic transfer.

There are no specifics in the measure that dictate how the kill switch requirement should be implemented, leaving that to the nationwide wireless industry that vocally resisted Minnesota's measure and others like it before reversing its stance last month and pledging to develop the technology for use across the country by next year.

Cellphone manufacturers and carriers have come under increasing pressure nationally to provide a means of disabling the costly electronic devices that have made their owners targets for thieves. Last month industry leaders agreed to develop smartphone software by 2015 that can remotely wipe a device and prevent reactivation by an unauthorized user. Such phones would still be capable of dialing 911 for emergencies.

Jamie Hastings, vice president of external and state affairs for the Cellular Telecommunications Industry Association, said that should be enough.

"Given the breadth of action the industry has voluntarily taken, we question if the Minnesota bill was unnecessary," he said. "State-by-state technology mandates stifle innovation to the ultimate detriment of the consumer."

Hastings said that the uniformity the industry relies on to provide security and choice to consumers could be threatened by piecemeal mandates.

Rep. Joe Atkins, DFL-Inver Grove Heights, the bill's sponsor, called the legislation a "belt-and-suspenders" approach to ensuring the industry follows through on its pledge. "I think whoever is first to get there and install kill switches on these devices will be very well-received by the public ... and it will probably be good for business as well," he said.

Minnesota's legislation could become a model for other states. A similar measure recently cleared California's Senate that would mandate the devices, but also fine retailers who sell devices without a kill switch. Locally, officials at Best Buy referred a request for comment to the wireless industry, while a Target spokesman said the responsibility for compliance likely will fall to carriers.

On the federal level, U.S. Sen. Amy Klobuchar, D-Minn., has introduced legislation similar to Minnesota's law. It's unclear how far along various wireless providers are when it comes to adapting to the technology. Apple's current technology already allows users to erase their phones remotely.

Raleigh, N.C.-based telecommunications expert Ben Levitan didn't mince words when he said the technology isn't necessary. "This is absolutely moronic," said Levitan. "This capability they're looking for has been a part of the phone system since 1988."

Levitan said kill switch technology amounts to the same power a cellular carrier has to shut off a phone when the bill goes unpaid. It's technology that he said is easily overridden by crooks. Effective theft deterrents, Levitan said, rely on tracking and enforcement.

"What is really needed is for law enforcement and phone companies to have a quick, legal way to track and recover phones," he said.

But the key focus of the drive behind the law is not recovery of property. Atkins said the impetus for the bill came at lunch with his sons, both U students, last year at a Dinkytown restaurant when he set his phone on the table.

"My oldest son said 'Dad you're going to get us killed,' and I honestly didn't know what he was talking about," Atkins said. "I was completely oblivious to what an epidemic smartphone theft was."

Abby Simons • 651-925-5043