LARRY MIREL was teaching a course in poverty law at George Washington University Law School when the idea came to him. One of Mirel's students was a retired lawyer who wanted to work for a poverty law program in Washington, but he was afraid that he didn't know enough about the subject or the procedures. More than that, the retired lawyer was afraid his younger colleagues would reject him because of his age.

But where the retired lawyer had a problem Mirel saw an opportunity to tap an available source of trained, swasoned legal talent. After a little preliminary work, he had a grant from the Department of Labor and was ready to give his idea a chance.

Mirel's idea could not have been simpler: On the one hand, Washington had any number of people who needed legal services of one kind or another but couldn't afford to pay for them. The demand for public interest lawyers far outstripped the apparent supply. On the other hand, of Washington's retired attorneys might want to keep a hand in their profession.

"There's a bug difference between slowing down and stopping," Mirel set about to marry the need for skilled lawyers with the supply of older men and women who wanted to perform a service for the community for little or no pay. With a little help from D.C. Bar, law schools and the D.C. chapter of the Federal Bar Associateion, Mirel sent out quesionnaires to retired D.C. lawyers asking if they were interested in doing any work in public interest law.

About 90 retired lawyers said they were interested in doing some kind of work-full-time, part-time, in court, research, without pay or in a few instances for the minimum wage-either on principle or to establish eligibility for Social Security payments. Eventually, Mirel found positions for between 40 and 50 of those lawyers who said they were interested. He might have place more, but he had some fairly firm rules that he followed.

Organizations who said they could use help had to have a clear idea what they were going to do with theiremeritus lawyers. Work space had to be available, along with necessary office support when needed. The atmosphere had to be dignified.

About half of the people Mirel has placed in Washington are working for the Legal Services for the Elderly program of the American Association for Retired Persons. Others are working for Friends of Superior Court, representing the interest of battered children when their parents appear in court.

A former National Labor relations Board attorney set up a hearing procedure for the United Mineworkers pension fund, at the fund's request, and then trained retired miners to serve as hearing examiners.

Mirel is convinced that there is no reason why his idea won't work in other parts of the country and for other professions. He has a grant from the semipublic, federally funded Legal Services Corporation to study the possibility of setting up pilot projects in three other locales-LosAngeles County, Cincinnati and in Iowa.

He has indications in Californa that the climate there is every bit as receptive as Washington's. During a recent visit, Mirel met a lawyer in his 70s who moved to California from the Midwest because his wife wanted to live in the sun. The lawyer, who had spent his professional life in courtrooms defending insurance companies, was being bored to death.

The man found his own solution. He walked into a Legal Services program office and voluntered his services. He now works from 8 a.m. until 6 p.m. five days a week drilling eager, but green, young lawyers in courtroom tactics. "He's teaching them the tricks of a lifetime, and they love him," Mirel said."And he's a happy man, doing what he wants to do."

Despite apprehensions expressed by Bar association officials that lawyers would object to cut-rate competition, Mirel says that no such complaints have been made.

In fact, he now is exploring the possibility of starting similar programs for other professions.

An engineer in Missouri, for example, is trying to put together an emeritus program for retired engineers.