MIRT: Outlawed Device Offers Lethal Tampering with Stoplights

Aug. 11, 2004

Imagine this: you’re running behind schedule and stuck in traffic. If only you could control those traffic lights, turning them all green as you approach, you could roll forward without interruption. Well, you can, but you’d better not.
Ever since early automobiles prompted the invention of the first traffic signal light, the science of traffic control has been the subject for mathematicians and city planners. It’s also been a hindrance for fire departments, ambulances, and police who have to get to their destinations in a hurry.
To facilitate the movement of those emergency vehicles, several “signal changers,” as they are called in the highway business, have been devised.
One type is sound activated, responding to the pitch of the sirens used by emergency vehicles. It’s illegal to mount a siren on a private automobile, though I read about a man who bought an old ambulance and turned on the siren when he was in a hurry. If you’re going to force the red signal to turn green, you’d better do it surreptitiously.
That rules out another of the methods used by emergency vehicles to trip traffic lights: those flashing lights on the roofs or fronts of emergency vehicles can also activate traffic changers set up to recognize the flash. Unfortunately, you can’t just flash your bright beams rapidly to imitate an ambulance. The sequence is too difficult to duplicate.
What’s left is the MIRT, the Mobile Infrared Transmitter. Like a super powerful TV remote, this gadget flashes a silent signal invisible to the human eye to change the traffic light from red to green.
Each of those remote control methods has its drawbacks. There are times when a siren isn’t appropriate. On foggy days or in heavy rain, the flashing light on an emergency vehicle might not activate the signal changer. The infrared beam of the MIRT is also limited by fog, mist, snow, and smoke.
Another option might be the radar activated detector, the tiny gizmos used in stores to detect stolen merchandise passing through the gate or at toll booths that recognize your car’s account and bill you for the fee without your having to stop. Maybe that’s the next step -- silent, invisible, and impervious to bad weather. Besides providing the GPS locator with information about the whereabouts of the emergency vehicle it could also trigger the traffic signal.
In the meantime, those gadget-loving folks who have already equipped their cars with radar detectors and police scanners can add one more, a MIRT. Available off the internet for as little as $100, these signal changers can be plugged into the cigarette lighter socket and sit on the dash, held by suction cups.
What if everyone had one? Chaos. Dueling MIRTs as drivers approaching the intersection at right angles each try to override the mechanical timing device of the traffic signal. In at least one reported incident, this conflict happened when the right of way of an ambulance was usurped by an illegal MIRT.
Illegal? Yes. Michigan, joining a number of other states, passed an ordinance banning use of MIRTs by all but emergency vehicles. Just when it was beginning to look like impatient drivers with extra cash could take control.
And I thought that traffic lights were simply timed by those gray boxes fixed to the light poles. Seems the traffic engineers, fire departments, ambulances and police had a built-in edge all the time.

Harley L. Sachs, www.hu.mtu.edu~hlsachs
Author of “Ben Zakkai’s Coffin” and “A Troll for Christmas” at ZumayaPublications, a series of Mystery Club cozies published by IDEVCO and Wings ePress, a techno-thriller “Scratch--out!” published by Fire Mountain Press, and short stories published by IDEVCO, Isaac Nathan, and Wescott Cove.