Chris Carpenter pitches for a team once owned by America’s largest brewery in a stadium that shares its name with a brand of beer. But should Carpenter wish to toast any of his victories this season, he’ll have to wait until he leaves the ballpark.

That’s because the St. Louis Cardinals don’t allow beer or other alcoholic beverages in their clubhouse. Same for the Colorado Rockies, who play at Coors Field, and the Milwaukee Brewers, who are not only named after beer makers but play in a stadium (Miller Park) sponsored by a beer company before a mascot who once celebrated home runs by plunging down a plastic slide into a huge faux beer mug.

So although the Red Sox caused a stir when new manager Bobby Valentine announced last month that his team would also be going dry, Boston was actually late to the non-alcoholic party since 18 teams — including the Dodgers, New York Yankees, New York Mets and Chicago Cubs — had already had their last call.

Last fall, officials in the commissioner’s office considered a league-wide ban on alcohol in the locker room, an idea that is still under discussion, a baseball official confirmed this week.

All this is good news for Jan Withers, national president of Mothers Against Drunk Driving, a group that for three decades has called for responsible drinking.

“Celebrities — and sports figures are major celebrities in this country — are role models. So it is an effective statement when they ban alcohol in the locker room,” she says.

“It really makes a difference. That they’re coming out and just making a clear statement to be safe. I am grateful to them for doing this.”

Baseball is not alone. In the NFL, where two Denver Broncos players were arrested on suspicion of driving under the influence in the last seven months, a long-standing league policy bans alcohol in the locker room. The NBA and NHL allow individual teams to set their own rules, with the Lakers, Clippers, Kings and Ducks all prohibiting alcohol in their dressing rooms. The Kings have gone even further, banning drinking on team flights as well as in their road hotels.

Those decisions were possibly influenced by the 1999 death of former Carolina Hurricanes star Steve Chiasson, who was found to have a blood-alcohol level more than three times the legal limit when his pickup flipped on the way home from a team party, throwing Chiasson from the cab and killing him instantly.

A similar tragedy four years ago led the Cardinals, Yankees and Orioles to ban alcohol from their clubhouses. Hours after a game at Busch Stadium, St. Louis pitcher Josh Hancock was killed when he drove a rented Ford Explorer into the back of a flatbed tow truck. His blood-alcohol level was found to be nearly double the allowable limit.

The Oakland Athletics didn’t bother waiting for a player to be killed. When pitcher Esteban Loaiza was ticketed for suspicion of driving under the influence on his way home from a game, GM Billy Beane immediately removed alcohol from the locker room.

And the Diamondbacks were even more proactive, banning liquor in their clubhouse three years ago “for liability reasons and to keep our players safe,” says team president Derrick Hall.

But aside from protecting players, the zero-tolerance policies are also sending a positive and socially responsible message, some league officials believe. Dodgers Manager Don Mattingly, who inherited a dry clubhouse at home when he took over the team two years ago, said public perception — shaped by such groups as MADD — has played a big role in forcing teams to act.

“In general, society has changed, which has changed baseball,” said Mattingly. “Now you go out and have a few drinks, you go, ‘I better drink some water for a while.’ I think society has changed in the way they look at DUIs and how dangerous they are.

“It makes sense at home. It really does.”

The Dodgers, like a handful of other teams, relax their rules on the road, where players generally take a bus back to the hotel.

The Angels, on the other hand, allow players to drink beer at work, home and away, even after losing a player to an alcohol-related accident three seasons ago. Pitcher Nick Adenhart was killed along with two companions when a minivan ran a red light and plowed into the car in which they were riding. Andrew Gallo, the driver of the van, was later convicted of murder and felony DUI.

“It’s about responsibility,” Manager Mike Scioscia said. “There are things that make you re-examine the policy in-house, but we haven’t experienced those things here.”

They experienced them in Boston last season, when pitchers Clay Buchholz, Josh Beckett and John Lackey reportedly ate fried chicken and drank beer in the clubhouse during games.

A few seasons ago, at least one Red Sox player confessed to drinking whiskey in the clubhouse before games.

But that team won the World Series while last year’s team lost 20 of its last 27 games, narrowly missing the postseason and sending the entire organization into a period of self-examination.

If the Red Sox had made the playoffs no one would have noticed, said Angels outfielder Vernon Wells, who agrees with his manager that the issue is mainly one of personal responsibility, not alcohol.

“If you’re responsible adults, you know what’s right and wrong, so it’s just a matter of being smart with your choices,” said Wells, who said he doesn’t drink anything stronger than Sprite in the clubhouse after games. “There are always guys who are going to make bad choices, and that’s on them. If you put the onus on the players, it’s their responsibility.

“But I don’t see anything wrong if you’re going to have a beer after the game.”