PICTURE this:

The federal government's Pell Grants program, which gives millions of dollars each year to needy college students, announces that it will no longer give scholarship funds to Blacks. When a Harvard senior whose education was funded by the program discovers that he is part Black, the government demands that he immediately reimburse them for the full cost of his education. This policy is enforced at universities nationwide.

Meanwhile, the Harvard administration, which stands to lose both top quality students and much-needed funds, takes no action to oppose the discriminatory policy--despite that its own rules flatly racial discrimination. And despite that its top administrators and Washington lobbyist have for years pressured the government not to cut back federal scholarship programs.

IF THIS fictional scenario seems far-fetched, consider the actual scenario: Thousands of college students, at Harvard and across the country, are being denied federal scholarship money because they are gay or lesbian.

Solely on the basis of their sexual orientation, these students are legally barred from receiving financial aid through the Reserve Officers Training Corps (ROTC). The policy's impact on Harvard itself was dramatically illustrated recently when David E. Carney '89, a Navy ROTC student described by his own commanding officer as "one of our best," revealed that he had discovered he was gay. The Navy suspended Carney from the program and is demanding that he come up with $50,000 to pay for his scholarship to Harvard.

Meanwhile, the University's response has been a deafening silence.

This isn't very surprising to anyone familiar with Harvard under the administration of Derek C. Bok. Since the Vietnam era, Bok has been wisely cautious about taking sides on public issues, on the grounds that doing so inhibits academic freedom and that a university serves society best by educating future leaders and attending to research.

But even Bok has sometimes found it appropriate for the administration to make statements and even lobby the government on public policy. In his 1982 book Beyond the Ivory Tower, Bok wrote such actions are justified when "university officials speak primarily for the purpose of protecting the interests of higher education."

Harvard even employs a vice president for government, community, and public affairs, as well as three officials responsible for "federal relations," including a lobbyist in Washington. In recent years, they have taken stands on numerous issues ranging from federal financial aid cutbacks to Reagan administration officials' attacks on higher education. Bok himself has spoken out publicly on such issues.

ROTC'S policy of discrimination calls for similar action because of the direct damage it inflicts on the University itself, as well as on higher education in general.

Needy students who cannot join ROTC because of their sexuality must seek assistance from other government and university scholarship funds, which are already spread thin. If such funding is insufficient, the students are left unable to attend the college of their choice. If they are granted scholarships, less money is available for others.

ROTC thus categorically bans about 10 percent of American college students from participation. In addition, it expels hundreds of gays and lesbians from the program each year, according to the American Civil Liberties Union. And now, it has chosen to persecute individual students at Harvard and other schools by asking them to pay back scholarship money.

At some of these other schools, administrators are going to bat for the victims of this discrimination. In response to the expulsion of a ROTC student at MIT, that university's provost is set to release a strongly-worded statement this week calling on the Defense Department to revoke the ROTC policy and admit gays and lesbians. Bok and other administrators here should do the same.

In addition, Harvard's Washington lobbyist should add ROTC's discrimination to the list of issues she discusses with government officials. And Bok, a respected figure in national education groups, should pressure these organizations to come out against the anti-gay restrictions. Unlike the racist regime in South Africa, for instance, ROTC is inextricably tied to American higher education, and its discriminatory policies are dependent on universities' continued acquiescence.

OTHERS in the Harvard community should put pressure on ROTC. At MIT, hundreds have rallied in support of the expelled ROTC student. At the University of Wisconsin, professors formed an anti-discrimination group that successfully encouraged the faculty to vote to suspend ROTC from campus in 1993 unless it admits gays and lesbians.

But, as Bok himself wrote in Beyond the Ivory Tower, "when universities address the government to protect the interests of higher education, their officials are the natural representatives to carry out the task. No one else can be counted on to have the knowledge and the motivation to inform public officials how their actions will affect the welfare of academic institutions."

The welfare of academic institutions and their students is now being harmed by unjust and arbitrary government actions. Bok is the natural representative to inform public officials of that fact.