From 1992 to 1997, the number of sport-utility vehicles on American roads doubled, to a whopping 13.8 million vehicles. In the same period, the category of "light trucks" (which includes pickups and vans) gained national hegemony, outnumbering cars for the first time. The result of the SUV craze is a marked decline in automakers' average fuel economy, from 25.9 miles per gallon (mpg) in 1988 to just 23.8 mpg in 1999.The cars going into America's junkyards today are more fuel-efficient than those in the showrooms, which was hardly Congress' intent when it passed the Corporate Average Fuel Economy (CAFE) law in 1975. CAFE, which holds car companies to a strict fuel economy limit and fines them if they exceed it, definitely worked--at first. From 1975 to 1989, the Sierra Club reports, the law doubled fuel economy. "It's clear that the standards have had a positive effect on fuel economy, which would be much lower had they not been in place," says David Greene, a corporate research fellow at the Center for Transportation Analysis and author of the report Why CAFE Worked. But as Americans buy 13-mpg Ford Excursions and Chevrolet Suburbans, mileage has been creeping backwards.Environmentalists champion a toughening of the CAFE standards, but fierce auto industry lobbying has kept that from happening for a decade. The rules, written at a time when most SUVs were used strictly as work vehicles, hold light trucks to a very loose standard (20.7 mpg, versus 27.5 mpg for cars). Efforts to close the SUV loophole have been stymied for four years by an anti-environmental rider to the annual transportation bill, which prevents the Clinton administration from even studying CAFE.Although the rider is still in place, it became apparent in late 1999 that the political ground is shifting. Environmental lobbyists alarmed the auto industry last September by lining up 40 U.S. senators to vote for a Clean Car Resolution calling for the rider's removal.The Sierra Club's Dan Becker, an energy campaigner, served on a Presidential commission that recommended raising the CAFE bar to 45 mpg for cars and 34 mpg for trucks. Although the pro-CAFE Congressional resolution did not pass, Becker says that signing on 40 senators was a major victory. "We definitely have the auto industry's attention," he says.The Club coordinated the mailing of 50,000 constituent postcards to home state senators urging an increase in CAFE, but a riled-up auto industry (aided in particular by Michigan's Congressional delegation), responded with a well-financed campaign to sway senators' votes in seven key states. Anti-CAFE ads paid for by the Alliance of Automobile Manufacturers and the U.S. Chamber of Commerce warned, with no real basis, that CAFE would abolish "full-sized" cars and trucks. One ad showed a rugged-looking farmer posing with his truck and strategically placed hay bales. "Farming's tough enough with healthy-sized pickups. Imagine hauling feed barrels around in a subcompact," the copy read. "Say No to a CAFE Increase."Michelle Robinson, a senior advocate for transportation at the Union of Concerned Scientists (UCS), says the CAFE freeze riders are themselves a sign of a worried auto industry. "They're concerned that the administration and the Department of Transportation might actually take some action," she says.UCS developed its own SUV, the Exemplar (a customized Ford Explorer), to demonstrate that it could get 28.4-mpg fuel economy and a 75 percent reduction in emissions by spending what amounted to $700 per car. "It just took some minor tweaks in the engine and other components," says Robinson. "The bottom line with the car companies is that they don't have to make their trucks more fuel-efficient, so why should they?" The domestic industry's recalcitrance is not shared by Honda and Toyota, both of which are introducing 60-mpg-plus hybrid cars on the U.S. market this year.It's not that the American automakers can't comply. Internal Ford Motor Company documents posted on a web site critical to the company (www.blueovalnews.com) revealed that Ford had completed research that would enable its trucks to be 15 percent more fuel-efficient, as well as meet the tough air-quality standards proposed by the Environmental Protection Agency.The Clinton administration has not been a leader in fighting for fuel-efficiency standards. Environmentalists urged President Clinton to veto the rider-bearing transportation bill, but he chose not to do so, despite alleged behind-the-scenes lobbying by Vice President Al Gore. In public, Gore has said nothing about CAFE, citing a need to follow the President's lead. His rival for the Democratic Presidential nomination, former New Jersey Senator Bill Bradley, has done more. In a September letter to the U.S. Public Interest Research Group, Bradley proclaimed the transportation rider "offensive," adding that it "has had the effect of allowing loopholes in the current law to mushroom."Gore's silence sends various signals. Environmentalists Becker and Robinson say they believe Gore to have been sincere in opposing the CAFE rider, and in arguing that case to President Clinton. But the auto industry thinks Gore is starting to "get it." An editorial in the Detroit News claimed that Clinton had passed on a veto precisely to benefit Gore's sputtering campaign in auto states like Michigan. "The auto industry may have found a friend in Al Gore, [who] won't brag about that, at least not while his environmental buddies are listening," the editorial said.A second front in the war against CAFE claims that the law is killing Americans by "mandating" they drive smaller cars. That was the theme of a lengthy piece in USA Today last July. More than 40,000 people died in crashes they could have survived in heavier vehicles, the newspaper claimed. The theory, cited by automakers trying to repeal CAFE altogether, ignores the fact that SUVs present significant rollover risk in accidents, making them just as dangerous overall as passenger cars.David Greene, whose work is supported by Oak Ridge National Laboratory, calls the dangerous small car theory "demonstrably false." Greene points out that cars were getting smaller and lighter before CAFE went into effect, and that a vehicle's distribution of mass is often as much a factor in crash survivability as is its size. Also, SUV occupants do well only when crashing into smaller vehicles (which often ride underneath the SUV's high bumpers). In one-car accidents and barrier crashes, he says, "It often doesn't matter how big your vehicle is--you can be dead, very dead or extremely dead. The bottom line is that if I buy a large SUV or pickup, I'm in effect imposing a safety risk on everyone else which might be greater than the safety benefit to me."For more information, contact the Union of Concerned Scientists: 1616 P Street NW, Suite 310 Washington, DC 20036 Tel. (202) 332-0900.