Adaptive cruise control systems could, it has been claimed, interfere with Garda speed detection equipment.
The system, available as an option on modern cars, automatically adjusts a vehicle's speed to maintain a safe stopping distance from the one in front. The technology, like ABS (anti lock braking) and ESP (electronic stability control) before it, could become a major advance in road safety terms.
It works by means of a device usually fitted behind the grille of the car. This device sends out a signal which "bounces" back from the car in front, enabling the vehicle's ECU (Electronic Control Unit) to calculate distance and speed, and adjust stopping distance accordingly.
Wayne Lyons, of Speedcameradefence, based in the North, claims that some automatic cruise control systems can disrupt the readings on hand-held Garda equipment, because of the beam emitted by the systems. It can, he maintains, produce the same effect as a piece of equipment sold ostensibly to open garage doors.
In practice, this device is most often bought by motorists eager to avoid speeding detections. It works by means of a laser beam that "jams" the speed detector, causing an error message to appear on the display, thus allowing the motorist time to adjust speed and avoid penalty points.
Peter Gay, of Tele-Traffic, the Warwick-based company that supplies the Ultralyte LTI - a laser gun commonly used by gardaí and British police - says that such equipment, used for the purpose of avoiding detection, is illegal.
This message, he says, could be construed by police as a sign that a jamming device is on board, and justify pulling the motorist over. In such a case, Motors assumes, the onus would be on the driver to convince the Garda of the device's purpose.
But could ticking the automatic cruise control box on the options list produce the same effect? Given that automatic cruise control technology is in its relative infancy, and different manufacturers offer different systems, could - in theory - the signal of a vehicle so equipped confuse things?
Gay maintains that the equipment supplied by his company is highly sophisticated - indeed, its US makers boast that their technology is used by NASA - and offers a high level of adjustability. "We could change the signal characteristics of the lasers. Our lasers operate at 904 nanometres," says Gay, "If that device [the source of interference] was operating at 904 nanometres, there could be a conflict. The laser software would say error, so you wouldn't get a speed reading, but we can change that."
When The Irish Times asked if automatic cruise control systems could definitely cause such a problem, Mr Gay said that the question required a response far more complex than a simple "yes" or "no"".
John Bolger, of BMW Ireland, thought the topic had a touch of urban myth about it, and that BMW's system - which operates by means of radar - could not interfere with laser-based detection equipment.
As far as radar-based speed detectors were concerned, adaptive cruise systems emitting on a given frequency were subject to strict licensing to ensure that they did not interfere with other apparatus. He pointed out that BMW has had adaptive cruise control available for three or four years, and he was unaware of any claims of such interference by the system. Jaguar and Mercedes, similarly, said they were not aware of any such instances.
A spokesman from the Garda Press Office said that the matter was not an issue, pointing out that adaptive systems were so uncommon. He added that, to his knowledge, there had been no such feedback from Garda operatives on the ground.
There had, though, been instances of people found with laser jammers, discovered by chance if a car was pulled over for some reason. As far as more focused methods of device detection are concerned, the spokesman said "obviously if a car goes by at 100mph and it doesn't register on your radar then there's something amiss".