BOSTON (AP) — A nationwide group of law schools, law professors and law students has sued the Department of Defense, alleging its requirement that law schools allow military recruiters on campus violates the First Amendment.

Many universities barred recruiters because they said the military’s ban on gays serving openly violated nondiscrimination rules.

But last year, the Defense Department threatened to pull federal funding from law schools that deny military recruiters open access to students. Faced with the loss of millions of dollars in federal funding, schools including Harvard, Boston University and Boston College backed off their bans.

Kent Greenfield, a Boston College law professor leading the suit, said the government is forcing schools to agree with its policies to get benefits, and that’s “not the American way.”

Plaintiffs also argue there are flaws in the 1996 law, called the Solomon Amendment, that permits the Defense Department to deny federal funds for institutions of higher learning which restrict military recruiting or ROTC on campus.

“The Solomon Amendment was passed to send the message that academic institutions were being too liberal,” Greenfield told The Boston Globe. “They are using this law to reach into the core of our educational philosophy and change it, and that’s contrary to the First Amendment.”

The suit was filed in U.S. District Court in Newark, N.J., and names Secretary of Defense Donald H. Rumsfeld and the secretaries of education, labor, health and human services, transportation, and homeland security.

US District Judge John C. Lifland held a hearing after an emergency request from the plaintiffs for a restraining order against the Solomon Amendment prior to the start of the fall recruiting season. Lifland gave the government a week to respond.

A phone message could not be left on a Department of Defense media line because the voice mailbox was full. An e-mail request for comment was not immediately returned.

Boston College, Harvard and Boston University are not party to the suit, the Globe reported. The organization Greenfield recently formed to file the suit, the Forum for Academic and Institutional Rights, declined to release the names of member schools. Greenfield said he wants to protect the schools from retribution.

FAIR’s board includes professors from schools such as Yale, Stanford, Georgetown, NYU, and the University of Southern California.

FAIR filed the suit along with the Society of American Law Teachers, student groups at Boston College Law School and Rutgers University School of Law and three Rutgers law students.

Law schools have treated military recruiters differently from private-sector recruiters for years because the organization that accredits law schools has a nondiscrimination policy that includes gays and lesbians. Recruiters were often still allowed on campus if invited by a student group.

Last year, the Defense Department began strictly enforcing the Solomon Amendment, writing schools to tell them they were out of compliance and faced loss of federal funds.

Laurence H. Tribe, constitutional law specialist at Harvard Law School, said the suit is “serious and very weighty.”

He said the Supreme Court has ruled the government can withhold funds from an activity it disapproves, but can’t deny those funds to an entire organization.

“This law is an attempt to take the principle that he who pays the piper calls the tune much further than the courts have generally allowed,” Tribe said.