ass device used to catch speeders
Monday, February 06, 2006
By NANCY H. GONTER
ngonter@repub.com

Northampton police officer Michael J. Allard has never lost an appeal when a speeder has been caught with lidar, a laser-based high-tech method for catching speeders.

Lidar, which uses laser instead of the Doppler radar police traditionally operate, is now used by many police departments including those in Springfield, Holyoke and Westfield. Officers who are trained in its use, say it measures speed accurately and easily.

"The LTI 20-20 Lidar is so trusted that it has been used on over six space shuttle missions to measure distances," Allard said.
Available many years but becoming more widely used, lidar - an acronym for LIght Detection And Ranging - uses a semi-conductor laser that uses distance and time calculations to measure speed of a target, in this case a potentially speeding vehicle. It can be used on vehicles up to 3,000 feet away and takes three-tenths of a second to make a determination.

State police began using lidar in 1995 and now have 160 lidar units in use statewide, said Trooper Stephen C. Mullaney.

"What amazes me is that NASA uses the same technology for tracking the space shuttle and the space station," Mullaney said.

Allard, who writes hundreds of tickets each year, said one woman he stopped for speeding in front of Walter Salvo House on Conz Street came to court prepared with extensive Internet research, which she presented to the Northampton District Court clerk magistrate.

Allard, a 17-year veteran and one of only three Northampton police officers certified to use lidar, won the case.

"Basically, I was challenged on the device, and I won," he said.

One of the benefits of lidar is it is difficult for speeders to detect. While a radar detector gives a driver a chance to hit the brakes, lidar does not.
"If a lidar detector goes off, it means you've had it," Allard said.

The beam of the laser is so narrow, unlike the wide band of the radar, that it makes it very easy to hit a specific target, even if it is in a crowd of fast-moving vehicles. It can even be used on a jogger or bicycle rider.

"I shoot the license plate or the grill. I'm looking for the best reflective surface," Allard said.
The lidar device not only tells how fast a vehicle is moving, but how far away it is from the device.

"In court, I can say where I was and I can say exactly where the car was," Allard said.

Other departments are also pleased with lidar.

Westfield police have two lidar units, one in each of their traffic cruisers. "It allows us to pinpoint cars in heavy traffic," traffic officer Richard P. Rix said.

In Holyoke, Police Chief Anthony R. Scott said he purchased about a dozen lidar devices shortly after being hired in 2001. Scott said state police told him the devices were more accurate than traditional radar guns for measuring individual vehicle speeds and would hold up as evidence in court.

"It tells you exactly how fast a car is going," Scott said. He said the hand-held devices are standard equipment for all cruisers and are used by the department's accident reconstruction team after serious crashes.

Springfield police Capt. Peter J. Dillon said his department uses lidar and continues to use radar. Lidar is great at getting speeds when there are multiple vehicles, he said.

"It's not, 'Gee, there were two other cars maybe it was someone else,'" Dillon said.

Northampton now has two lidar units which cost between $3,000 and $4,000, compared to the $600 to $2,000 for traditional radar. Each Northampton patrol car is equipped with radar and the department has four hand-held radar units.

Staff writers George Graham and Dave Reid contributed to this report.