To prove the law's success, supporters like MADD point to what they say is an estimated 23,000 lives that the elevated drinking age saved from drunk driving.
The law supports the organization's mantra that "the sooner youth drink the more likely they are to become alcohol dependent and to drive drunk."
However, McCardell disagrees that the drinking age contributes to safe driving.
"The drinking age has little do with [drunk driving]," said McCardell. If that were the case, he has argued, the better solution would be to raise the driving age to 21.
Although the number of drunk-driving fatalities has decreased with the new law, McCardell says these statistics ignore the effects of improvements in seat-belts, airbags, and public information campaigns against drunk driving, highway construction and regulation laws.
While the drinking age is not the only way to save lives, critics still defend its role.
"The number one way to reduce death in drinking and driving is airbags," said George Mason's Anderson. "[But] the drinking age did make a difference. It's part of the puzzle, and I hate to throw out parts of the puzzle."
However, McCardell also highlights the adverse effects of the current law, such as the disenfranchising of parents in the alcohol coming-of-age and the underground fake I.D. business. Youth are no longer introduced to alcohol in a controlled environment, because many states prohibit parents from providing alcohol to their children at home. Instead, many law-abiding students must first encounter alcohol at college parties.
McCardell proposes lifting the cap for states that lower the drinking age while pursuing pilot alcohol education programs, as long as the states keep drunk driving rates down.
Some young people believe alcohol education classes might encourage responsible drinking among college students.
"It would be giving an indication that they're given a seat at the table," said Zack Yost, a senior at University of Michigan and president of the Michigan Student Assembly. "I think that students might find it empowering."
But public health professionals predict dangerous consequences will accompany lifting the law.
"If you make alcohol available to 18-year-olds, you have to think of the consequences of your actions," Wechsler said. "You're bringing it into high schools."
An industry-wide effort to sell alcohol to younger people would likely follow the change. But most importantly, "we're going to have the same increase in deaths as we had before, about 800 or more," Wechsler said.
Scientists also fear the effect on the brain, which does not complete development until the mid-20s. Others bemoan missing the chance to address the emotional, social, cognitive and physical reasons students drink heavily.
"It's jumping at a simple solution to a complex problem," Anderson said. "It's like a doctor giving a pill to someone with depression."
Implicit in McCardell's plan is a recognition that 18 to 20 year olds will drink, regardless of the law.
"Alcohol remains real in the lives of 18, 19 and 20 year-olds, but it is present not in open but behind closed doors" McCardell said.
Although many students agree that alcohol is intrinsic to campus social life, some dispute the ill effects of allowing their under-21 peers to drink legally.