Of the games drivers play, it's one of the most hair-raising.
A lead-footed motorist will "stretch the green," as traffic engineers like to say, and speed through an intersection in defiance of an aging yellow or even a freshly lighted red traffic signal.
Sometimes, the driver behind will accelerate and follow, cruising blithely through the red. Occasionally, the next driver will scoot through, too, and maybe a couple after that -- all of them gambling that side traffic will hold back until the intersection is clear.
Most of the time, nobody gets hurt. But experts agree that it's a very nasty habit.
About a decade ago, public and private traffic safety experts in major cities -- including Baltimore -- began to complain about what they saw as a perilous trend: A significant fraction of drivers seemed to be slipstreaming through red lights in defiance of the law and, it seems, common sense.
"Some of it is right-turn-on-red violations, where they don't stop before making the turn," said William F. Zorzi Sr., public relations vice president for the American Automobile Association of Maryland. "Some people drive like you can make a right turn on red without stopping at all, without looking."
The number of tickets Baltimore police write each year for red-light violators has remained between 6,000 and 8,000 over the past eight years. Statewide, 28 people died in accidents caused by red-light runners in 1990, according to Maryland State Police statistics.
Some safety experts say drivers apparently began "stretching the green" because the nation's rising crime rate meant that police had less time to enforce traffic laws; because the pace of life has accelerated, breeding impatience; and because Americans became more skeptical about traffic signs and lights that seemed overly restrictive.
"It's part of the hurry-up, aggressive nature of our society today," said Cody L. Godman, president of the Safety Council of Maryland. "Everybody wants to be first. Nobody wants to wait."
Some think compliance with traffic signals in the Baltimore area will not improve without a massive police crackdown.
"Police monitoring of intersections is probably the only way to reduce the number of people who violate traffic signs and signals," Mr. Godman said.
But, he added: "It's almost an impossibility for the police to do that with great effectiveness. They can't sit at intersections all day."
There is some disagreement over how serious a safety threat red-light runners pose.
"It's a dangerous damn practice, you know?" said Mr. Zorzi, a sometime crusader on the topic. "The other guy assumes he's got the full green, and the other guy comes out of nowhere."
But in the March 1990 edition of the magazine Public Roads, Martin T. Pietrucha, a traffic engineer now at Pennsylvania State University, and three other researchers reported that most drivers who disobey traffic signals and signs appear to do so in a way that creates few hazards.
As part of a study for the Federal Highway Administration, the authors tracked 79,055 cars passing through 156 intersections in New York, California, Virginia and Texas. They found that about 1 percent ran red lights. Of those violators, only 11 percent drove in such a way as to cause other motorists to slow, turn or stop, creating at least the potential for an accident.
Although about a quarter-million vehicles were observed, Dr. Pietrucha said in a recent interview, no accidents were witnessed.
Red-light violators, the authors reported, seem to act only after calculating the risks. And, the authors reported, most seem to "assess risk correctly and act prudently."
But, Dr. Pietrucha said this week, his study did not show "stretching the green" is always safe, particularly at poorly designed intersections.
PTC Sometimes people make errors in judgment, and these can be hazardous. "It's not the kind of behavior we want to encourage, OK?" he said.
But neither is there much data suggesting a vigorous new enforcement effort is needed, some traffic safety experts said.
"I have no real data that shows it is worse than it's ever been before" or even that it constitutes a serious problem, said Sam Yaksich Jr., executive director of the American Automobile Association Foundation for Traffic Safety in Washington.
To launch a major red-light enforcement effort, he said, would require shifting scarce money and manpower from enforcing seat-belt, drunken-driving and other traffic safety laws.
Even if running red lights is not a major cause of accidents, Mr. Zorzi responded, the practice should not be tolerated. "That's a poor way to drive defensively, to think that, 'Everything's clear, so I'm going through the red light,' " he said. "That's just not right."
Tony Petralia, a veteran accident investigator with the Baltimore police, knows just how unsafe running a red light can be.
Patrolman Petralia, who works the night shift, was driving his 1986 Nissan pickup home at 3:20 a.m. one Saturday last November when he was rammed by another pickup charging through a red signal at Lakewood Avenue and Orleans Street.
Smelling gasoline spilling out of a ruptured tank, the 17-year veteran policeman sawed himself out of his jammed seat belt with a serrated knife fetched from someone's kitchen drawer.
Then he waited anxiously, his knees and chest throbbing, as firefighters used a pry bar to pop open his jammed driver-side door.
"I've investigated a lot of accidents where people got burned up, and believe me, that's not the way I want to die," he said.
There was no fire. But Patrolman Petralia, now 37, underwent knee surgery and spent more than two months recuperating from the accident.
The driver who ran the light had been drinking and smoking marijuana. But Patrolman Petralia said he writes plenty of $45 tickets to otherwise law-abiding drivers who run red signals stone-cold sober -- later giving him excuses like "the pizza was getting cold" and "I have to go to the bathroom."
One strategy that traffic departments across the nation have used to combat red-light runners for at least the past several years is the so-called "all red" signal. This means that all four lights at a four-way intersection are red for about a half-second to 1 1/2 seconds.
This gives drivers "stretching the green" a little more time to clear the intersection.
Richard Moore, chief of traffic engineering for Baltimore County, said that about 20 percent of the county's signalized intersections use all-red periods. But he said engineers are reluctant to expand the practice because drivers seem to have adapted by running the red lights later.
"Our biggest fear with this is the more we use it, the more the public's going to get used to it because they know it exists, and it will lose its effectiveness," he said.
Leading causes of accidents
Motorists running red lights (in legal language, the violation is "failure to obey a traffic signal") in Maryland caused:
* 2,454 injuries -- 5th-largest number
* 28 deaths -- 6th-largest number
* 3,771 accidents -- 7th-largest number
In this chart, the leading causes of accidents in Maryland in 1990 are sorted by total number of accidents for each category.
Cause or violation.. .. .. .. .. ..Accidents..Injuries..Deaths
Failure to reduce speed.. .. .. .. .21,942.. .12,017.. .. 73
2. Failure to yield right of way.. .. .17,562.. ..9,947.. .. 83
3. Outside single lane.. .. .. .. .. .. 8,246.. ..3,476.. ..113
4. Speed too great.. .. .. .. .. .. .. .7,683.. ..3,711.. .. 61
5. Crossing center line.. .. .. .. .. ..4,575.. ..2,303.. ..122
6. Outside designated lane*.. .. .. .. .4,317.. ..1,369.. .. 27
7. Failure to obey traffic signal.. .. .3,771.. ..2,454.. .. 28
8. Improper turns.. .. .. .. .. .. .. ..2,951.. ..1,156.. .. .1
9. Backing in roadway.. .. .. .. .. .. .2,894.. .. .449.. .. .3
10. Failure to obey stop sign.. .. .. ..2,175.. ..1,338.. .. 11
* The vehicle causing the accident failed to obey signs reserving lanes for specific purposes, such as "Left Turn Only" and "No Trucks in Left Lane."