A long battle between left-wing and conservative faculty members at Harvard Law School has reignited with the recent denial of tenure to two left-wing scholars and a commencement week sit-in by the law school's first tenured black professor.

At commencement yesterday, some law students wore yellow armbands to protest the denial of tenure last month to Assistant Prof. Clare Dalton and David M. Trubek, a visiting scholar from the University of Wisconsin. Some distributed leaflets saying that the ceremonies were "tainted" and that the tenure denials signaled "the end of academic freedom at Harvard Law School."

The law faculty voted 29 to 20 to grant tenure to Dalton, four votes shy of the necessary two-thirds majority required for a tenure recommendation. Trubek was denied tenure personally by Harvard University President Derek Bok who, in an unprecedented act for the law school, overrode the faculty's favorable tenure recommendation.

Both scholars are associated with a school of legal thought known as Critical Legal Studies (CLS). As described in a news release by some of its members, CLS "holds that the legal system's appearance of neutrality is merely a mask for bias in favor of the rich and powerful."

The Dalton and Trubek dispute is, in the view of some faculty members, the most divisive manifestation of the faculty split over whether the law school faculty is becoming overloaded with CLS proponents.

Although several CLS adherents have been awarded tenure, the faculty voted last fall against promoting a CLS adherent, Assistant Prof. Daniel Tarullo -- the first time in 20 years an assistant professor had been denied tenure.

The more conservative faction has accused Dalton and Trubek of shoddy scholarship and poor teaching; the liberal wing said that opposition to both scholars stemmed from fear of their politics.

Dalton has asked Bok to review her tenure case and retained a well-known Boston civil rights lawyer, Nancy Gertner, to represent her in a possible sex discrimination suit against Harvard.

"If I had been only a woman or only identified with CLS, I might have made it through," she said. "The problem is that I am a woman and ideologically incompatible with my more conservative colleagues."

This week, Prof. Derrick A. Bell Jr., who described himself as sympathetic to the Critical Legal Studies Movement, staged an 80-hour sit-in to express his "disappointment and shame" over the law school's actions.

Applying to Harvard Law School the tactic he once used to desegregate lunch counters, swimming pools and bowling alleys, Bell remained in his Langdell Hall office from Monday until last night, sleeping on a chaise longue he brought from his Cambridge home and putting out a guest book for visitors to sign.