And, he says, when colleges do act on lawsuits and compensate parents, "a zippered mouth is part of the settlement agreement."
John McCardell, former president of Vermont's Middlebury College, who started the initiative, agrees that liability "has to be one of the things a president thinks about." But he rejects the idea that legal concerns are the primary motivation of the idea.
Alcohol, he says, is a "reality in the lives of young adults," and the age 21 law "forces it underground and off campus where there is great risk."
He wants to bring college drinking out into the open, where colleges can better control it.
Holmgren, who saw saw firsthand the dangers of the college drinking culture, says she sees the logic in the proposal.
"You finally get your independence and you go crazy," said Holmgren, who says her drinking moderated when she became legal. "If you're allowed to drink whenever, it demystifies the whole thing."
The so-called Amethyst Initiative has refocused the debate on what parents, law enforcement, colleges and even the students themselves are calling a binge drinking epidemic that needs to be fixed.
"All the data show that by the time they go to college they have already experienced alcohol, so how can anyone say the law is working?" McCardell asked.
McCardell says he has received numerous letters after going public with the initiative showing many "parents are in our camp."
But MADD's Levy counters, "Colleges are not willing to be the bad guy and parents want them to."
Minimum drinking ages were established in the United States after the repeal of Prohibition in 1933. When the voting age was lowered from 21 to 18 in 1971, many states dropped drinking ages to 18 or 19. But in 1988, after studies showed an increase in alcohol-related auto accidents involving 18- to 20-year-olds, all 50 states raised the age back to 21.
As a result, alcohol-related fatalities have dropped 56 percent from an all-time high in 1988, according to studies by the National Institute of Alcohol Abuse and Alcoholism (NIAAA). The greatest decline was in the 16-20 age group.
"Colleges have an obligation to address this," said Dr. Ralph Hingson, NIAAA's director of epidemiology and prevention research, who conducted the updated studies. "But they can't do it alone. It's a larger social problem to address harmful drinking."
Not only must colleges set limits, according to Hingson, but "key forces" in society must intervene – offering screening and counseling interventions, mandated treatments, ignition locks so drunk drivers cannot operate a car, setting lower blood alcohol limits and even raising the price of alcohol, which discourages students with less discretionary income.
"We need to all work together – college presidents, professors, students, deans and alumni along with city officials," Hingson told ABCNews.com.
Christopher B. Gilbert, education law attorney at Bracewell and Guiliani in Houston, said public universities are largely immune from liability suits, but that doesn't mean parents have not tried to hold them accountable.
He understands the need for colleges to exert more control, but said the issue is complicated by a double standard.
"I have a problem with the country saying to people, you can send them off to die in Iraq, but you can't drink," he said. "It's a little patronizing. Not all people are mature at 18, but some aren't at 21."