The very technology that has for years allowed fire trucks, ambulances and police cars to emergencies faster - a remote control that changes traffic signals - is now much cheaper and potentially accessible to civilians.
No bigger than a dashboard radar detector, the device is known as a mobile infrared transmitter, or MIRT, and can be had for about $300. The possibility of its proliferation is unnerving public safety and transportation officials.
"It has the potential to be a huge problem," said Steve Misgen, a Minnesota Department of Transportation signal operations engineer.
MIRTs are the triggers in so-called "traffic pre-emption systems," which are comprised of two parts: a receiving device mounted on a stoplight and an infrared transmitter normally placed in emergency vehicles that has a range of about 1,500 feet.
The technology has been used for about three decades and is widely deployed. A U.S. Department of Transportation survey of the nation's 78 largest metropolitan areas last year found them at about 26,500 intersections across the nation.
A cheaper MIRT available since January from FAC of America, which is based in Fridley, Minn., costs less than half the previous price of other devices that go from $650 to $1,000.
The company's president, Tim Gow, insists he has strict safeguards against MIRTs falling into unauthorized hands and that its affordability helps public safety officials with tight budgets.
"We get requests from individuals, but the answer is no," he said. "This is a lifesaving piece of equipment."
So far, law enforcement agencies report no problems from the devices. But traffic engineers and some politicians are concerned, and a check of eBay found some of the cheaper devices for sale on the Internet.
Last month, they caught the eye of a committee of traffic engineers from the Minnesota Department of Transportation and communities around the Twin Cities. Though many cities and states have laws against interfering with traffic lights, Misgen said the committee likely would recommend that the state legislature specifically outlaw the devices for unauthorized users.
In Michigan, a state legislator has promised legislation to make the devices illegal.
Gow, an electrical designer, has been in business for about 20 years. He said his company would sue any unauthorized person who uses its devices.
But a handful of MIRTs were being offered for sale on eBay when The Associated Press checked Monday. And kits for building similar devices are also available online.
One of the eBay sellers first indicated they would sell the device to anyone. However, in response to a follow-up query, the person said they would sell only to authorized users. The seller declined an interview.
The primary makers of traffic pre-emption systems, 3M Co. and Tomar Electronics Inc., offer encryption technology that can lock out unauthorized devices - but it is far more expensive than systems that operate in the clear.
Systems that offer encryption run roughly $2,500 per unit higher than those that don't - a considerable expense for any cash-strapped municipality if it were to be forced to retrofit traffic signals.
It's not clear just how many cities have the encryptable devices. The Institute of Transportation Engineers in Washington, D.C., said there's no way to tell, and a 3M spokeswoman wouldn't comment on how many cities bought devices before encryption was available.
If transport officials were to become locked in a technology arms race with infrared transmitter outlaws, the costs could be high. Most major cities don't put pre-emption devices at every intersection, but there are plenty: Minneapolis, for example, has about 900 traffic lights, of which city traffic officials say about 40 percent are pre-empted.
Misgen, the state engineer, said only a handful of the 640 traffic lights he oversees in the Twin Cities area are fitted with the module that allows encryption.
"This might be a huge expense for cities, counties and states," he said.
By Travis Reed