A teenager on a bicycle is weaving in and out among several pedestrians on the sidewalk when he is summoned by a police officer.

"You know you're not supposed to ride a bicycle on the sidewalk," the officer barks at the youngster.Without further provocation, the boy pulls a handgun and fills the officer with lead.

What should the officer have done to protect his own life and the lives of others nearby?

This particular scenario is not real, but is like many real situations where officers have to decide when and if to shoot at a suspect to protect their own lives and possibly the lives of bystanders.

As a test of officers' field judgment in particularly stressful situations, the Utah Department of Corrections has developed a "Shoot - Don't Shoot" training program that allows officers to interact at close range with 21 potentially violent scenarios to see whether they will shoot at images on a video screen that may shoot back.

Officers working in the field choose to shoot about 80 percent of the time, said training officer Grant Larsen. More seasoned officers who have administrative duties shoot closer to 60 percent of the time.

"The officer on the street is more in tune with life and death situations. Administrators are more conscious of consequences that could happen" after a shooting, like a lawsuit, said Larsen. There's no right and wrong to every scenario, but deciding to shoot in 80 percent of the scenarios is about right, Larsen said.

The scenarios, which were filmed like scenes from Hill Street Blues or Cagney & Lacey, are projected on a large screen in the indoor shooting range at the Fred House Training Academy in Draper. Officers play the role of a backup officer, watching the situation develop until they decide to either shoot or let the drama play through.

"We haven't used it with new recruits; basically it's for officers that have been on the streets for a while," said training specialist Grant Larsen.

Narcotics raids, traffic stops and family disturbances are among the taped scenarios.

One situation shows officers looking for a dangerous suspect along a railroad track when a man walks toward them while ignoring repeated commands to stop. He reaches behind him and draws a dark object - still approaching. Several seconds pass before the officer sees the man unfold a wallet with a card inside that reads: "I am deaf and dumb."

Trainers can rewind the video and match holes in the newsprint-covered screen with the video image to judge how accurate an officer shot. But the main purpose of the video training is to test an officer's judgment - something that can't be determined as well on a regular shooting range where officers plug away at silhouetted targets 50 feet away.

The tape is stopped after each situation and the officer is asked to explain why he shot or didn't shoot. Either decision can be correct depending on the explanation the officer gives for the choice he made.

The officer is also asked to account for the number of rounds fired. "If he gives a good reason for emptying his gun it's OK," Larsen said, but trainers keep a close eye out for situations where an officer either shoots too many rounds or doesn't shoot at all.

A group of reporters were invited to the range Tuesday to see the program and do some actual shooting. Beads of sweat lined their foreheads as the pressure of making the right decision in front of their peers mounted. One reporter shot the deaf man before he had a chance to display the wallet.

In 1974, Larsen was on a narcotics raid in Salt Lake City when there was an exchange of gunfire. "My partner was killed, and we killed the suspect." This kind of experience gives Larsen helpful perspective as a training officer. He also hopes reporters will better understand the stress officers are under in a shooting situation.

Several federal law enforcement agencies and all of the Salt Lake area police departments have had a chance to train with the video equipment, Larsen said.