Derrick A. Bell Jr., professor of Law, has threatened to resign if the Law School does not substantially increase its efforts to hire minority faculty.

Bell, who is the only black professor at the Law School, put the threat in a confidential letter to his colleagues last month.

Bell confirmed yesterday that he sent the letter, but refused to discuss its contents.

Walter J. Leonard, special assistant to President Bok, said yesterday that Bell's letter was "well thought-out, rather lengthy, and I thought rather good."

Leonard, who is on leave as an assistant dean at the Law School, said that Bell urged the Law School to search harder for qualified minority faculty members. He said that Bell's threat was "an observation that he might be called upon" to resign if such a search did not occur.

'Saddened'

"At first I was somewhat saddened by his letter," Leonard said. "Then, too, I could understand the great pressure that he, as the sole and only black professor at the Law School, is under."

Leonard said he hoped Bell would reconsider his possible resignation, but he urged the Law School to "recognize its responsibility to seek out black professors and other minority professors that are not represented."

"I don't accept as a fact that there are not other black professors in the country that meet the kind of criteria that Harvard sets for its faculty," Leonard said.

Of 59 Law School faculty members, one is black, one has a Spanish surname and two are women. Of 16 teaching fellows, one is black and one has a Spanish surname. The Law School also has a black associate librarian and a black assistant dean of admissions and financial aid.

William L. Bruce '46, vice dean and affirmative action officer of the Law School, said yesterday that the Law School's appointments committee is "really making an intensive effort" to recruit minority members, but that recruitment is difficult.

"When we find the people we want, other people have found them," he said. "The people you want have a good many splendid opportunities open to them."

Most Law School professors and lecturers contacted yesterday refused to comment on Bell's letter or the issues it raised.

"This is a private letter, and I think it would be very unfair to Professor Bell to discuss it," James Vorenberg '48, professor of Law, said.

"I think there are some things that are important to hash out individually," Maurice D. Ford '58, lecturer on Law, said.

Stanley S. Surrey, Smith professor of Law, said Bell's letter was "just a candid description of his position, which he wanted to share with his colleagues."

"I think the problem is a difficult one, and I think everyone perceives it as such," Surrey said.

Albert M. Sacks, dean of the Law School, and President Bok could not be reached for comment yesterday