A large Washington law firm-Shaw, Pittman, Potts & Trowbridge-has been forced to apologize to a Yale Law School senior after a student-faculty tribuna found one of its partners had asked her "discriminatory" questions focusing on her being a Puerto Rican.

The tribunal found the questions, asked during a recruiting dinner, violated Yale rules against discrimination. The questions, according to the tribunal, included: 'Do law firms do a disservice by hiring minority students who the firms know do not have the necessary credentials and will then fire in three to four years? Would I have been admitted to the law school if I were not a Puerto Rican? Was I culturally deprived?"

In a letter of apology this week, Shaw Pittman's senior parnter, Ramsay D. Potts, called the questions by Martin Krall "insensitive and regrettable", and acknowledged "they may have had a chilling effect on the firm's recruitment of minorities and other students.

But Potts said that neither the firm nor Krall had "discriminatory motives or intent."

Krall asked the questions of Sonia Sotomayor de Noonan, a resident of the Bronx, N.Y., who had graduated from Princetown before going to Yale Law, during a dinner in New Haven Oct. 2 with several other Yale students.

The next day, according to the tribunal report, Sotomayor challenged Krall during her formal interview over what she considered the discriminatory nature of the questions. He said he didn't mean any harm and invited her for further interviews in Washington.

She refused-giving up her chance to work for the firm-and instead filed a formal complaint against Shaw Pittman.

Since then the debate over the Washington firm's actions have raged across Yale's campus with letters and petitions being posted on bulletin boards with wall posters in Peking.

Yale's Black Student Union, LatinAsian-Native American Association and Yale Law Women joined the fray on the side of Sotomayer and three recent Yales graduates now working at Shaw Pittman were chastized by Associate Dean James W.Zirkle for attempting to influence the official tribunal.

As an indication of the strong feeling in the law school, the tribunal rejected the first letter of apology by Potts because "the firm did not seem fully to recognize the consequences of its partner's action."

If Shaw Pittman had not written a satisfactory new letter, it could have been barred from recruiting at Yale. Byond that, though, word-of-mouth reports of the incidents circulating at Yale and other top law schools may do more to harm the firm's recruiting than formal sanctions, said Zirkle.

The incident illustrates the stiff competition among big laws firms for the best graduates at top-ranked law schools such as Yale. The firms are willing to comply with rules against discrimination to avoid losing recruiting privileges or getting a bad reputation among top students.

Potts, for instance, said the incident "prevented us from recruiting her (Sotomayor), which we wanted to do.It also probably prevented us from recruiting other students.

The incident rocked the 50-lawyer firm, which has a large number of Yale graduates among its partners and associates. Although not one of the best-known Washington firms, Shaw Pittman is highly respected here and does a usual Washington administrative law practice.