Cape Girardeau police Sgt. J.R. Davis trains the telescopic sight on an approaching vehicle, curved metal stock pressed into his right shoulder, finger poised on the trigger and then -- ZAP -- speeding ticket.

Davis has been familiarizing himself with one of the police department's newest weapons against speeding motorists, a laser gun. Radar guns emit a wave of sound to measure speed; laser guns use light.

Davis, who heads the traffic division, said the department has had the laser gun for about a year. He and another officer are certified to use the gun and are in the process of compiling 30 hours each with the tool so they will be eligible to train other officers.

The laser has advantages over the Doppler radar guns the department currently uses: It shoots a narrow beam of light that will allow officers to precisely locate motorists in traffic.

Davis said experienced officers using radar guns can identify speeding vehicles in traffic. But radar guns send out a broad wave of sound and are not as accurate in traffic.

The laser beam is a narrow, low energy beam that is not affected by natural light. It will work just as well in broad daylight as it will at night.

"The infrared light that these transmit has 20 times less energy than your home remote control does," Davis said. "It's not like if I turn it on you it's going to cut you. It's not that kind of laser."

But the laser gun has some disadvantages. Right now the guns are priced at more than $3,000 a piece. Davis said radar guns can run between $1,500 to $2,500 each.

Also, the laser gun is heavy and has to be hand-held. Officers must be stationary when using the laser gun, and it cannot be mounted on vehicles. The gun has a metal gun stock attachment that makes it easier to use.

There are devices that will detect the use of a laser gun, but Davis said buying one would be a waste of money. The laser beam is so narrow that the officer would have to hit the detector to set it off.

"The only thing the detector would do is tell you when you've been caught," he said.

Davis said the department does not plan to replace radar guns with laser guns. The laser will compliment the department's radar guns and be used with them. The tool also has the ability to measure distances. That feature helps reconstruct accident scenes.

Davis said when measuring distances the laser is hooked to a special instrument that looks like a scientific calculator. The calculator records all the measurements, which are then transmitted to a program in Davis' office computer. The program takes the data and turns out a detailed representation of the accident scene.

Cape Girardeau Police Chief Rick Hetzel said one of the department's greatest concerns is to reduce the number of auto accidents in the city. "We recognize that is a serious community problem," he said. "Speeding is the most common complaint that I receive from our citizens."

Hetzel said the laser gun is one of many tools the department may begin to utilize over the years. Another is photo-radar guns that have a camera mounted on a stationary radar gun. The device records vehicle speeds and takes a picture of anyone surpassing the legal limit.

The license plate of the car is viewed when the picture is developed. Then the picture and a traffic citation are sent through the mail to the driver's home.

Hetzel said that device may be tested in the area in about three months. The laser gun has already been in use. Davis spent part of Monday on Highway 74 monitoring traffic.

"The laser gun is a continuation of our desire to use technology to make our streets safer," Hetzel said.