Cruising along Riggs Road in Hyattsville on a recent night, Prince George's County police Cpl. T.P. Hammill spotted an easy target: a Toyota Corolla without a license plate, driving around in the dark with its lights off. Hammill flashed his lights and blared his siren. The Toyota slowly pulled over.

Suddenly and unexpectedly, however, the driver jumped out and advanced toward the patrol car, sparking a confrontation. Hammill shouted at the man to put his hands in the air. A few tense seconds later, the driver complied. Hammill approached the driver and frisked him. He didn't find a weapon.

After a few minutes, calm was restored. The man, an immigrant from Sierra Leone named Paul Idriss, explained that he had received his driver's license just a few days earlier. Puffing anxiously on a cigarette, he confided to a reporter that he panicked when he realized a police officer wanted to stop him on a dark street.

"I was very nervous, very nervous, especially when I saw he was white," Idriss said, pointing toward Hammill, who gave him a $30 citation. "So many things came through my mind. You hear all these stories about how police treat drivers and other people."

Such minor traffic stops are becoming increasingly common across the country but especially in Prince George's County, where the odds of getting stopped by police have soared. And while law enforcement officials tout the stops as an effective way to fight crime, the practice has raised hackles among many drivers who say that it borders on harassment.

In Prince George's, police have nearly doubled the number of motorists they pull over annually on the highways, from about 37,800 in 1994 to 71,100 last year. Firm numbers are hard to come by in other jurisdictions; police in the District and Montgomery and Fairfax counties said they do not keep statistics on traffic stops.

But experts say the number of traffic stops has climbed in most areas since 1996, when the U.S. Supreme Court ruled that it is legal for police to stop drivers for minor traffic violations, even if the officers' real intent is to search a car for drugs or guns or for some other reason.

In the past, traffic stops generally were limited to catching speeders, drunks and other bad drivers. Now, authorities are embracing traffic stops as a way to prevent crime. For example, patrol officers in Prince George's are being trained to use even trivial infractions -- such as failure to use a turn signal -- as a legal excuse to pull people over and poke around their cars with flashlights.

Police say the tactic deters crime by putting crooks on notice that they could be stopped at virtually any time and subjected to a search. "We're giving people what they're asking for, which is a uniformed police presence in their community," said Prince George's Police Chief John S. Farrell. "And it's been enormously effective in reducing gun violence."

Even the police acknowledge, however, that the strategy carries risks. Traffic stops can quickly turn dangerous or deadly -- for both sides.

Montgomery County officials are still reeling over an incident in April in which a patrol officer fatally shot an unarmed motorist in the back after a brief car chase. A group in Prince George's County has held weekly rallies over the past month to protest the 1993 death of Archie Elliott III, 24, who was shot 14 times by District Heights and Prince George's police while he was sitting handcuffed in the front seat of a patrol car.

The most frequent complaints about the increase in traffic stops come from law-abiding citizens who grumble that they are being detained for little apparent reason, limiting their freedom of movement.

Reginald Simmons, a 22-year-old Hyattsville resident and a recent graduate of Howard University, said Prince George's police pulled him over four times last summer while he was driving his 1987 Ford Mustang. His alleged offense? Driving a car with a dim license tag light.

Simmons said the fact that he was driving with an out-of-state license plate, albeit legally, apparently also raised the officers' suspicions. And while Simmons said the officers never gave him a ticket and didn't treat him rudely, he said he's still angry that police had repeatedly forced him to sit on the side of the road for a half-hour at a time when he hadn't done anything wrong.

"How do they justify treating me like a criminal when I haven't broken the law?" he said. "All I wanted to do was go on a date, have a good time and not have it all ruined by getting pulled over for no reason. One time my girlfriend really got upset with them. She leaned over on the driver's side and said, `Why are you pulling him over all the time?' "

Prince George's police officers say they don't stop drivers unless they have a legitimate reason, and they are quick to point out that they, too, are vulnerable during traffic stops. "You walk up to that car, there's a chance that the window opens and -- bang! -- you're dead," said patrol officer Tony Cancino.

In many communities, the debate over traffic stops has centered on race. Minorities often complain that patrol officers stop them on the highways based primarily on the color of their skin, an illegal and widely disputed practice known as "racial profiling."

In Montgomery, County Executive Douglas M. Duncan (D) has asked his police department to study whether officers are unfairly targeting minorities in traffic stops. In Anne Arundel County, Police Chief P. Thomas Shanahan also has promised to investigate how his officers hand out tickets after black residents complained that they were being discriminated against.

State police in Maryland, New Jersey and North Carolina also have been criticized or sued for racial profiling after statistics strongly suggested that black drivers were being singled out for stops and searches.

Nerves are especially sensitive in Prince George's, where many residents of the majority-black county have long regarded police with suspicion. Complicating matters is the fact that officers make the most traffic stops in high-crime neighborhoods that also happen to be predominantly black.

As a result, Prince George's police say they are going to extraordinary lengths to treat residents fairly.

As part of a special traffic-stop operation called Take Away Guns, which began two years ago, patrol officers hand out letters that explain the program before they ask drivers for permission to search their vehicles for firearms. The letters also list the name and phone number of the local district commander, and encourage aggrieved motorists to call if they have questions or complaints.

Farrell said the effort is paying off. Citizen complaints about police misconduct during traffic stops have actually dropped -- from 27 in 1994 to 10 last year -- even though the number of drivers who were pulled over increased by about 88 percent during the same period, according to statistics provided by the department.

Overall complaints about police misconduct also have declined sharply in recent years, from 166 complaints in 1994 to 88 last year, according to the department.

"What we've done is show that increased traffic stops and reduced citizen complaints are not mutually exclusive," Farrell said. "But it's not just the numbers. It's also the perception in the community that their police department can be effective without being an oppressive or occupying force."

Some community leaders have strongly endorsed the traffic-stop campaign. Alfred Barrett, president of the Glassmanor Citizens Association, said residents of his Oxon Hill neighborhood don't mind being stopped if it helps police crack down on crime.

"I've told our citizens that in order to catch the bad guys, the good ones are going to have to do some suffering along with them," said Barrett, who has been pulled over twice for a broken taillight. "I know it's inconvenient to be stopped. I recognize that. But our community has been plagued by drugs and trafficking for a long time, and we support what the police are trying to do about it."

Resentment is building in other corners. Blanche H. Lee, a 72-year-old great-grandmother from Mount Rainier, said she still is angry over how she said she was treated by a Prince George's police officer who stopped her on Queens Chapel Road one Saturday in May last year when she was driving home from a matinee.

After she couldn't find her vehicle registration in her glove box, Lee said, the patrol officer accused her of driving a stolen car. Flustered, she said, she then complained that she was being harassed. In response, she said, the police officer threatened to throw the book at her.

"That's when he really got smart," said Lee, who received a citation for failing to produce a registration card on demand. "He said, `You better keep your mouth shut or I'll give you even more tickets.' I couldn't believe it. I'm a senior citizen, and he was treating me like a drug dealer."

Lee said that she called the officer's captain to complain but that nothing came of it. "All he said was, `Well, you must have done something to make [the officer] angry.' "

Edythe Flemings Hall, president of the Prince George's County branch of the NAACP, said she is skeptical about the police department's assertion that complaints have dropped. She said her office receives 10 or so complaints each week about police behavior, most of them related to traffic stops.

Most people don't bother to file complaints with the police, Hall said, because they assume the department will ignore them. "The last thing you want to do is go to the police department and ask an officer for a form to file a complaint against another officer," she said.

To prevent confrontations between citizens and police, the NAACP has asked Prince George's officials to install video cameras in all patrol cars. The police department agreed in principle to the request last month, saying that they would seek money -- perhaps in the form of a federal grant -- to buy and install the cameras in about 900 cruisers.

MORE TRAFFIC STOPS IN PR. GEORGE'S

Since 1992, Prince George's County police have more than doubled the number of motorists they pull over for traffic stops each year, largely because of a stepped-up campaign to deter the flow of guns and drugs in high-crime neighborhoods. At the same time, recorded citizen complaints about police misconduct have declined.

Year: 1992

Traffic stops: 33,302

Total citizen complaints: 181

Complaints from traffic stops: 19

Year: 1993

Traffic stops: 37,013

Total citizen complaints: 187

Complaints from traffic stops: 21

Year: 1994

Traffic stops: 37,799

Total citizen complaints: 166

Complaints from traffic stops: 27

Year: 1995

Traffic stops: 47,747

Total citizen complaints: 156

Complaints from traffic stops: 17

Year: 1996

Traffic stops: 45,051

Total citizen complaints: 126

Complaints from traffic stops: 17

Year: 1997

Traffic stops: 65,289

Total citizen complaints: 121

Complaints from traffic stops: 13

Year: 1998

Traffic stops: 71,068

Total citizen complaints: 88

Complaints from traffic stops: 10

Source: Prince George's County Police Department

CAPTION: Prince George's police Lt. Andrew Ellis explains the Take Away Guns traffic operation to Cesar Diaz, who got a ticket for a broken headlight in Langley Park. Under the program, officers ask to search their vehicles for firearms.