The combination gas stations and convenience stores at this exit of Interstate 10 are jammed each day by workers leaving the nearby chemical plants and oil refineries.

It is not gasoline most of the people are after. They head straight to the tubs of iced beer, rum and vodka.

"Everybody's too hot and thirsty to wait until they get home for a cold beer," said Chuck Johnson, who stopped to stock up for the drive home. "I get two for the road. I've been doing it for years, and I'm not about to stop."

The Louisiana Legislature, in an effort to stop drinking and driving, has passed a law that will go into effect in August, making it illegal for passengers in moving vehicles to possess an open alcoholic drink.

Louisiana drivers are already forbidden to have open booze, but police said that, because passengers are exempt, a driver could simply hand his drink to somebody else in the car.

Police concede the new law will be broken regularly in this land of drive-through daiquiri shops, go cups, all-night bars and ever-present alcohol.

"In Louisiana, we drink to celebrate births and drink to mourn deaths," said Ronnie Jones, a former state trooper who now teaches criminal law at Tulane University. "We drink early, and we drink late. We drink all day long for any reason. And an awful lot of people keep drinking in a car."

According to figures compiled by Mothers Against Drunk Driving, 48 percent of the 938 fatal accidents in Louisiana in 2000 (454) were alcohol-related. Alaska, Delaware, Massachusetts, Montana and New Mexico had higher percentages, but all had far fewer total accidents. Texas -- with 3,779 fatal accidents, of which 49 percent (1,841) were alcohol-related -- is the only state that had more accidents and a higher percentage.

"We're always right up there on top," said Cathy Childers, Louisiana executive director of MADD. "We're hoping it will be a deterrent. It's so sad to drive up to a light and see people in the next car drinking alcohol. Maybe it will be one small step toward raising children who don't grow up thinking it's all right to drink and drive."

The law allows a number of exceptions. For instance, passengers in licensed limousines, taxis or hotel courtesy vehicles are exempted. A provision exempting people in parked cars ensures the legality of college football tailgate parties in which drinking is heavy.

Those caught in violation will be fined $100, but catching scofflaws will be difficult, said Lt. William Davis of the state police.

"It will take very careful observation by our troopers or other law enforcement personnel," Davis said. "It's likely that we'll find violations when we stop people for other infractions. It's really tough to spot someone drinking in a car."

The bill, which had been opposed by the state's convenience stores and alcohol lobbies, did not encounter opposition this year.

"Primarily, we didn't feel this was going to have any impact on highway safety," said Chris Young, a lobbyist for the Louisiana Association of Beverage Alcohol Licensees. "We think it's a waste of time. It's already illegal for a driver to possess or consume alcohol, which we supported. If our highway safety figures have not improved in the future, we'll go back and ask the Legislature to repeal it."

Tulane's Jones, who served as chairman of the governor's DWI task force in 2000, is also doubtful that the new law will have much of an effect.

"I'm not certain that the open-container law will reduce drinking and driving," Jones said. "It won't change a lot of attitudes, and most people don't get drunk in their cars. They get that way and then get into their cars. That's what we need to stop."

The law is not hurting business at the many daiquiri shops that sell the frozen drinks to motorists.

"Not at all," said Matthew Young, manager of Daiquiri Chef, where drinks with names such as "Cobra," "White Russian" and "Jungle Juice" sell from $3.50 to $12 for a giant Mardi Gras mug. "When I sell them, they're in a closed container."

The cups are capped with a plastic lid with a spot in which to insert a straw. Until the straw is inserted, the drink is considered closed.

"I keep an unused straw in my car," customer Ami Henderson said. "If I get stopped, I just whip out the used one and show them the new one. Looks like a closed container then."

Drinking-and-driving opponents fear that, like Henderson, many people on the road will just hide their drinks, not give them up. But they also hope that the new law will be at least a small step toward sobering up Louisiana motorists.

"It reflects the culture that has been here for a long time," said John King, executive director of the Council on Alcohol and Drug Abuse of Greater New Orleans. "Drinking is part of life. The problem with that mind-set is that they don't see a rolling car as any reason to stop the party."

"Not at all," says Matthew Young of Daiquiri Chef when asked if the new law on alcoholic drinks has hurt his business. Before heading home after work, Ronald Arso of New Orleans buys a drink in a closed container from Daiquiri Chef in suburban Kenner, La.