Seeing the Light. Then Again, Maybe Not.

THE way the New York City public advocate, Betsy Gotbaum, sees it, Officer Russel Timoshenko might be alive today if it weren't for tinted car glass. In July, the officer was shot and killed, and his partner, Herman Yan, was wounded by assailants hidden from view by the dark tinted windows of an S.U.V.

"Police officers are putting their lives on the line every time they approach a car with blacked-out windows," she said.

As a result, Ms. Gotbaum has called for stricter tint laws, hoping to make New York State's already restrictive limits on window tinting even more imposing. But even though New York has one of the toughest tint laws in the nation, it and other states have found it difficult to get cars with dark windows off the streets because of exceptions to their own rules and conflicting federal standards.

Window tint laws can be confusing partly because there are federal standards and state standards, and each state has its own. (The International Window Film Association's state law chart is at iwfa.com/industry.htm.

There are also different rules for trucks, including S.U.V.'s. Worse, because of differing state laws, a darker tint that is legal in, say, Connecticut, could get you a ticket while driving through New York.

Car manufacturers live by the rules of the National Highway Traffic Safety Administration. All car windows from the manufacturer must allow 70 percent of visible light through. What people think of as untinted car windows are actually a 70 percent tint. The federal rules for trucks, which includes S.U.V.'s, are less stringent. They are required to have a clear windshield and front windows.

Back and rear windows can be tinted to any darkness if the vehicle has side mirrors. Almost all factory tints are pretty dark, allowing in only about 20 percent of the light.

The National Highway Traffic Safety Administration determines what qualifies as a truck based on its intended use. "There is a little bit of wiggle room as to what you can classify as a truck," said Bob Dallos, an engineering group manager for General Motors. For instance, the Chrysler PT Cruiser is classified as a truck.

Once owners get their cars from the dealer, they are held to state tinting standards. New York, for example, keeps the federal standard of 70 percent for all but the rear window, meaning owners cannot tint the other windows at all. The rear window can be tinted to any darkness if the car has mirrors on both sides

But there is a Holland-Tunnel-size loophole. Cars classified as multi-passenger vehicles can have any tint on the back and rear windows, provided the vehicle also has side mirrors. By New York statute M.P.V.'s are described as any vehicle "designed to carry 10 persons or less and constructed either on a truck chassis or with special features for occasional off-road operation."

That comprises a broad variety of vehicles including S.U.V.'s, minivans, limos and trucks.

In New Jersey, no tint may be applied to the front driver or passenger window of cars or S.U.V.'s. The rest of the windows can be tinted to any darkness if the car has two side mirrors. Cars in Connecticut may tint front and back windows as long as 35 percent of visible light comes through the tint. Back windows can be any darkness provided there are two side mirrors. For S.U.V.'s, only the front windows are held to the 35 percent standard; back and rear windows can be tinted to any darkness as long as there are two side mirrors.

Less stringent states, particularly those in the Sun Belt, allow darker tint. In Arkansas, front and back windows and the top of the windshield can let through as little as 25 percent of visible light.

Automakers put their tint right into the glass, but aftermarket tints are films applied on the windows with adhesive. There are two broad categories of window films with different characteristics: those that reflect light and those that absorb light. Reflective films are metallic; absorptive films have dyes, pigments or ceramics in them.

States also vary on how reflective a film may be and the allowable color of the tint. Some have a medical exception that lets drivers use extra-dark tint if a doctor says they are sensitive to light.

While cars with tints that are legal in their home state can be ticketed in a more restrictive state, state troopers said they are unlikely to stop a car for illegal tint alone. For example, a law in Georgia that would have enforced tint laws only on cars registered in the state was thrown out in court as discriminatory against residents. The tint law now applies to cars passing through Georgia, but the police say they largely don't enforce it. Nor is New Jersey's law widely enforced.

"It's a violation of our motor vehicle law, but are we going to cite you each and every time you come through the state? No," said Dennis Hallion, a New Jersey state trooper and chairman of the National Troopers Coalition.

Still, the law gives some lawyers civil rights concerns. "It's one of those traffic regulations that lets police search anyone, anywhere, whenever they want to," said Albert Alschuler, a professor of law at Northwestern University Law School in Chicago.

The bill to tighten New York's law is being drafted by State Senator Eric Adam of Brooklyn, a former policeman. The proposal includes amending the law to prohibit unlimited tinting of the rear windows and including tint as an item on annual car inspections. It would increase penalties on drivers, including a 0 surcharge, money that would go into a fund for officer safety and training and for enforcement, and penalize shops that install illegal window films. It would also require shops to record the license plates of cars it tints, the license of the driver buying the tint and the darkness of the tint installed.

Shops said the proposal would be a hardship. "It would pretty much crush the automotive tinting business in New York State," said Jim Murphy, owner of Putnam Window Tint in Mahopac, N.Y. Mr. Murphy, who said his shop tints about 1,200 vehicles a year, said he would support a limit of tint that allows 50 to 35 percent of visible light through.

Car owners say they like the tint because of the way it looks, the privacy it provides and the way it protects skin and upholstery from the sun while keeping the car's interior cooler.

John Cervoni, 44, of Bayside, Queens, was stopped twice for illegal tint in the last six months. Mr. Cervoni said he paid the tickets and kept the film.

"It's like ," he said, "and it's a small price to pay to keep a 0 tint job."