Raymond Momboisse calls himself a public interest lawyer, but other public interest lawyers call him a wolf in sheep's clothing.

Momboisse's 18-lawyer firm the Pacific Legal Foundation, has fought efforts to protect endangered species and has opposed rules banning toxic chemicals. It has battled civil rights groups seeking affirmative action.

Thanks to the Pacific Legal Foundation, California's nuclear moratorium was declared unconstitutional. The firm supported the right of automobile companies not to install airbags.

Momboisse's firm, with offices in Washington, D.C., Sacramento and Seattle, is the largest of a new breed of conservation, business-oriented public interest law firms. A dozen such nonprofit groups have sprung up to counter the influence that liberal public interest lawyers have gained over government policy.

These new firms are goading the old-guard liberals at a time when public interest law is facing unprecedented challenges: a cutoff of foundation grants, an attack in Congress, and, more worrisome, a cooling of the idealistic passions that fired up thousands of young lawyers in the 1970s to work "pro bono publico" -- for the public good.

Public interest firms have grown from 15 a decade ago, to some 115 today. Nationwide, they employ 650 lawyers to represent poor people, minorities, women, the elderly, the mentally handicapped, prisoners, homosexuals, consumers and the people whom Assistant Attorney General James Moorman calls "the breathers, as opposed to the polluters."

In a short 10 years, groups such as the Environmental Defense Fund, the National Prison Project, the Mexican-American Legal Defense and Education Fund, the Media Access Project, the Natinal Veterans Law Center, the women's Legal Defense Fund have profoundly altered the way decisions are made in the federal government.

"In the 1950s, it was assumed that government lawyers were public interest lawyers," says Moormam, formerly with the Center for Law and Social Policy. "Then people started thinking that the beneficiaries -- the people who breathe clean air -- should have the same power to influence decisions as the polluters. This triangular 'public interest model' of government is far better than the earlier 'regulated vs. regulator model."'

Public interest firms won landmark court cases, forcing Congress to lack statues, prodding agencies into creatng programs. A single case, brought by the NAACP Legal Defense fund, forced Congress to spend $30 million and double the size of the Health, Education and Welfare Department's Office and of Civil Rights.

With a Democratic administration, public interest lawyers have been named to high positins, often in the very agencies they once sued.

Given such a record, the public interest law movement might rest on its laurels. Instead, it is undergoing something of an identity crisis.

The Ford Foundation, which has been the largest backer of public interest law, is pulling out to encourage the firms to become self-sufficient. Ford poured $21 million into 10 firms since 1969. Those with a solid membership base, such as the Natural Resources Defence Council which has 40,000 contributors, will recover. Smaller groups, such as the Citizens Communications Center, which represents civil groups on broadcasting issues, could go under.

"We've never been stretched thinner," said William Butler of the Environmental defence Fund. "We're trying to do a good job, but the tide is turning against us both in Congress and in the admistration."

Ira Glasser of the America n Civil Liberties Union, the granddaddy of public interest law firms, complains that civil rights issue "aren't fashionable among white liberals anymore. No one hears the victims screaming now. You can't turn on the news and see George Wallace at the schoolhouse door."

Disillusionment with the power of the courts is causing many public interest law groups to put more effort into lobbying Congress, monitoring agencies and organiizing grass-roots campaigns.

"There's an atmosphere of circling the wagons and hunkering down for a long siege," Harvard Law Professor Abrahan Chayes told a recent conference of public interest lawyers. But he exhorte them, "If not you -- who? Not your law school classmates who are getting $200 an hour for climbing commons out of bond indentures."

Bond indentures, however, and corporate practice generally, have appartently regained the popularity they lost during the do-gooder 1960s and 1970s. Law firms report that applicants rarely ask about the firms' pro bono activities anymore.

"Desolation now stalks so many of the law schools," Ralph Nader complained. "Too many professors are out consulting for big business. Students' valutoo many professors are out consulting for big business. Students' value systems are shaped by Covinton & Burling. You don't hear talk in the corridors about the corporation crime wave.

If the future looks gloomy to Nader, Raymond Momboisse couldn't be more pleased. Dressed in a three-piece navy blue suit with a read silk handkerchief, momboisse told a crowd of public interest lawyers recently that the conservation law firms are "the wave of the future."

"It is said we are not a public interest law firm," Momboisse said. "(But) who is more unrepresented than the silent, hard-working taxpayer? The little man who foots the bills for the great social experiments of bloated bureaucracy -- we represent him."

With its $2 million budget and generous corporate board members, he said, "Pacific Legal Foundation is here to stay . . . We believe in progress and development. We don't believe in lowering expectations. We certainly don't believe profit is immoral."

Faced with a public opinion climate that seems to favor less government rather than more, the liberal public interest firms are increasingly frustrated as they look to government for support.

The administration has been thwarted in Congress on a bill that would have required all agencies to pay attorneys' fees for public interest firms that sued and won. Several statutes allow courts to award fees, especially in civil rights cases. However judges are often unreceptive; one federal judge recently awarded fees amounting to $4.50 an hour in a complex consumer case.

"The public doesn't understand that when corporations use the federal government, they are financed by the federal government because legal fees are tax-deductible," said Joseph Onek, deputy White House counsel and a former public interest lawyer. Public interest firms do not have that advantage, he added.

Public participation programs, through which agencies such as the Federal Trade Commission pay interested parties travel and research money to join in their regulatory hearings, have been cut back in Congress.

In what may be a healthy trend in the long term, many public interest lawyers are turning to their colleagues in private practice. While big law firms seem less enthusiastic about pro bono work than in the past, both the New York City Bar Association and the American Bar Association are discussing plans to require private attorneys to donate 30 to 50 hours of work a year to good causes.

Former attorney general Ramsey Clark, a veteran public interest lawyer, opposes mandatory schemes but urges all private lawyers to tithe their incomes to public interest causes -- which for some lawyers is "like working in a napalm factory all week and then marching in a peace parade on Saturday," he said.

A Washington-based group called the Equal Justice Foundation already is collecting pledges from lawyers and law students.

To survive, public interest law will require a change of values on the part of private attorneys, said Clark, whose New York firm does half its work for free and limits the income of senior partners to $50,000 a year.

"We're going to have to redistribute lawyers' times," he said. "Do we have to make $100,000 a year to be a success?

The young lawyers who joined the public interest movement in the '70s, are older now. They have mortgages and children and they are making a third of what their law school classmates earn.

"It's unseemly for people of our ability to spend so much time shaking a tin cup," said Mark Lynch of the American Civil Liberties Union. "A lot of us are going to have to grow up and cross the bridge into private practice. Many lawyers have done a lot for the public interest without being fulltime public interest lawyers."

Looking to private firms for time and money may be more realistic, he suggested, than looking "for some old-fashioned New Deal way to pull it out of the public hat.