RICHMOND, NOV. 27 -- The last high-level state support for Virginia Military Institute's all-male admissions policy collapsed today, as Attorney General Mary Sue Terry asked a judge to let her withdraw from defending the school in its battle against the federal government.

Terry's request, if approved by U.S. District Judge Jackson Kiser, could leave the VMI Board of Visitors with no attorneys defending it against a U.S. Justice Department lawsuit seeking to force the taxpayer-funded school to admit women.

Terry said this afternoon that Gov. L. Douglas Wilder last week eliminated the legal argument she had planned to offer on behalf of VMI when he ended a long silence and declared he was prepared to testify in court against the academy in rural Lexington.

That left Terry -- who as the state's top legal officer represents VMI and all other state schools and agencies -- with a conflict of interest that she said could be resolved only by removing herself from the case. VMI may be entitled to a private lawyer at state expense, Terry said, but she said that decision must be made by Wilder.

Wilder declined to comment today. Last week, Wilder said he was considering withholding state money appropriated for the defense of VMI.

Terry's announcement capped a week in which Virginia's statewide elected officials parachuted out of the VMI controversy, a politically charged case that has pitted loyalists of the 151-year-old school against a growing body of opponents who say the single-sex policy is not defensible.

After Wilder, who told VMI graduates last May that "VMI has been too good for too long for me to intervene now," joined the opponents, Terry likewise seized a chance to make her exit.

"Both saw the writing on the wall," argued Mary Washington College political scientist Mark J. Rozell. "Doug Wilder's flip-flop on the issue provided Mary Sue Terry with a convenient opportunity to make her move politically."

Terry, who already is lining up support for a run for governor in 1993, said politics had nothing to do with her decision. "If political considerations had been the driving force," she said, "I wouldn't have been in the case from the beginning."

Terry said she still believes that VMI's policy is constitutional, but that her case was undercut when Wilder took the opposite view. "Until or unless the General Assembly holds otherwise, his is the final word," she said.

There's no guarantee that Kiser, who has been hearing the case in the federal courthouse in Roanoke, will agree, some legal experts said.

Kiser already has rejected a request from Wilder that he be removed as a defendant in the case. Given that, said George Washington University law professor John Banzhaf III, "I am not sure he's going to let Mary Sue Terry off that easily."

Even if Kiser lets Terry leave the case, he could order the state to pay for private lawyers for VMI. Joseph M. Spivey III, chairman of VMI's Board of Visitors, said in a statement that he will ask Wilder to hire outside counsel for the school.

The VMI Foundation, a private group that raises money for the school, also has joined the suit to defend VMI's admissions policy. Robert H. Patterson Jr., a lawyer for the foundation and VMI alumnus from the class of 1949, maintained that the withdrawal of support by Wilder and Terry does not severely weaken the school's case.

"The issue of constitutionality is the sole province of the federal court, where we are now positioned," Patterson said.

Patterson declined to comment on whether VMI supporters might donate money to pay for a defense if the state refuses to pay.

Obern Rainey, a spokeswoman for the Justice Department, declined to comment today.

From the beginning, Terry and the VMI Foundation took different courses in their defense of all-male admissions.

The VMI Foundation argues that the school's program, with its intensive hazing of young men in close-knit barracks living, is unique and would be destroyed by the enrollment of women.

Terry holds that VMI is not unique since women can take military training courses at Virginia Tech in Blacksburg, and that VMI is merely an additional option under an umbrella of diversity in the state's system of higher education.

Terry, in a letter to Wilder, said the VMI Foundation's lawyers were "openly hostile to the defense we offered."

But Patterson said, "We have never viewed it that way."