The Senate Judiciary Committee yesterday concluded its hearings on the nomination of Edwin Meese III as attorney general and scheduled a vote for next Tuesday after the head of the government ethics office defended a controversial letter saying Meese had not violated the federal standards of behavior.

Two staff attorneys in the office had concluded earlier that Meese did violate some standards in not disqualifying himself when two men who had helped him financially were considered for federal jobs.

David H. Martin, director of the Office of Government Ethics, denied yesterday that he had overruled the two attorneys, Nancy Feathers and F. Gary Davis, in sending a contrary declaration to the committee.

Instead, he testified, the three had reached a "mutual decision" to reverse the lawyers' initial finding that Meese had committed three violations of federal rules. Martin also said he was not pressured to decide that Meese had behaved ethically. "I have experienced no pressure by anyone in the executive branch," he testified.

He also defended his decisions to alert White House counsel Fred F. Fielding that his staff had reservations about Meese's behavior, then to make no mention of those reservations in his letter to the committee.

"I didn't think it was proper" to notify the committee of what the staff lawyers had found, Martin said during the third day of confirmation hearings.

However, he said, "I did the proper thing by notifying the agency" where Meese works, meaning the White House, where he is counselor to the president. "We resolve a lot of problems with a lot of nominees, and if we do resolve them we don't raise them in a certification letter."

Martin's testimony was followed by that of Feathers and Davis, who also said they were not pressured to change their findings and were now satisfied that Meese had acted ethically. "There were certainly no threats; we weren't coerced; there were no inducements offered," Davis said. Later, he added that he probably had "misconstrued the facts" in one of the cases.

But former Watergate prosecutor Archibald Cox, who testified next for the lobbying organization Common Cause, told the committee he found it "unbelievable" and "frightening" that the ethics office had concluded that Meese acted ethically.

Most observers say they believe that the Republican-controlled committee will vote to confirm Meese next week. The nomination then will go to the floor, where no vote is expected until the Senate returns from recess Feb. 18.

The Office of Government Ethics was established in 1978 under the post-Watergate Ethics in Government Act to monitor the behavior of federal employes and help prevent conflicts of interest. The office also notifies the Senate whether persons who must be confirmed for federal jobs have violated any of the government's ethical standards.

Martin, who is a lawyer, said he does not have "any particular background in ethics." He became head of the ethics office after the 1980 election. "I was interested in serving in the Reagan administration," he said. "I met President Reagan when he was campaigning . . . and I was thoroughly impressed with his vision of America."

Feathers and Davis' report concluded that Meese violated the standards by failing to disqualify himself from a meeting where his accountant, John R. McKean, was approved for a seat on the U.S. Postal Board of Governors. McKean had arranged two loans for Meese totaling $60,000. Yesterday, Davis testified that he finally decided that Meese did not violate the standards in that case because McKean arranged the loans for Meese but did not provide the money himself.

Sen. Howard M. Metzenbaum (D-Ohio) asked Davis what difference it made whether McKean was the trustee of the loan or the lender. "Does it matter whose money it was?" Metzenbaum asked.

It might not matter "when you take the overall pattern," Davis said. "But when you talk violations, you have to be very careful, and we try to be."

Davis and Feathers initially also said the McKean case was a violation of the rule that officials should avoid creating the appearance of impropriety. But later they decided not to call the action an "appearance violation."

"We call it an appearance problem," Martin said. "If you want to call it a violation of an appearance standard, you can call it that."

Martin said the "appearance standard" was "aspirational in nature." He said he felt that he had done his job by mentioning the problem to Fielding because Meese would be alerted to such problems in the future.

Later in the day's hearing, Cox of Common Cause said he did not agree that the "appearance standard" was "aspirational."

"You must get your terms right," Cox said. "I think that if there is an appearance of impropriety, there is an impropriety," because not even the person in question can tell whether he was influenced by the apparent conflict of interest.

The staff lawyers also initially concluded that Meese probably violated a rule prohibiting officials from receiving gifts from subordinates because McKean forgave Meese some interest payments for a time. Yesterday, Davis said he had misconstrued the facts in this case because McKean was not the lender, therefore not the person who forgave the loan, a fact pointed out to him by ethics office chief counsel Donald Campbell.

In their initial report, the lawyers also cited Meese's failure to disqualify himself from a meeting at which a friend, Thomas J. Barrack Jr., who had helped with the sale of Meese's house in La Mesa, Calif., was approved for a high-level job in the Interior Department.

As a result, the lawyers said, Meese may have violated a rule prohibiting government employes from engaging in activities that might create the appearance of giving preferential treatment.

They did not spell out in yesterday's session why they eased their stand on this issue. But Meese's lawyer, Leonard Garment, had sent a memo to Martin saying Meese was not fully aware, at the time of the Barrack appointment, of Barrack's role in the sale of the house. Barrack not only found a buyer but put up part of the money Meese was paid.

The lawyers' 16-page report was based on an examination of a 385-page report by independent counsel Jacob A. Stein, who investigated Meese last year and did not find evidence of criminal misconduct. Stein did not comment on Meese's ethical conduct.