Mayor Mayor Barry yesterday took on the nettlesome issue of ethics in government, saying he has ordered city officials not to accept free travel or similar gifts from city contractors, even in cases where such gratuities are legal.

Barry, whose administration has been stung by corruption charges and ethical improprieties by high officials, said that the city's conflict-of-interest law is unclear on the point of what officials can accept and that he has ordered a study of ways it might be tightened.

The mayor added, however, that he will continue to accept political contributions from firms doing business with the city as he prepares to seek reelection to a third term this year.

Barry, who relied heavily on contributions from city contractors in his 1982 reelection campaign in which he raised a record $1.3 million, said "I'm not going to apologize" for raising large sums this year, including funds from firms with city business.

"I am not going to fall for that political enemies' tactic," Barry said. "They say, 'The mayor is out here raising money. He ought not to raise all this money.' But if the law says you can raise $2,000 the contribution limit for an individual or firm , what's wrong with that? If it's reported, what's wrong with that? I am raising and my finance committee is raising money because people believe in this city and believe in me."

Barry, while saying "we have the strongest conflict-of-interest law of any city," said the law is "fuzzy" and "unclear" about when city officials can accept free travel expenses from city government contractors and when it is prohibited.

The mayor, speaking at his monthly news conference, was responding to a question about the recent disclosure that city Public Works Director John Touchstone and his executive assistant Marie Timm accepted a total of $1,720 in free travel and hotel expenses in 1984 and 1985 from Datacom Systems Corp., a parking consultant firm that has two public works contracts.

Barry said he has decided not to discipline Touchstone because he did not intentionally violate the law. "I think in Mr. Touchstone's case he wasn't clear on what the law is," the mayor said.

Barry said that when two city officials responsible for interpreting the conflict-of-interest law -- Keith Vance, the director of the city Office of Campaign Finance, and Inspector General Vernon Gill -- tried recently to explain it to top city officials, "they couldn't really agree."

Barry said he has asked the city's lawyers to suggest revisions that would clarify the law, which he will then recommend to the City Council.

Nonetheless, Barry said, "I have said to all my department heads and all of the staff who work for the city government under my control: 'You are to travel out of agency budgets regardless of what the law says . . . . If you don't have money in your budget to travel, don't travel.' "

In response to a question, Barry said he will not make public his personal income tax returns.

On another topic, Barry said that an internal police investigation has pinpointed the source of leaks that led to the failure of Operation Carribean Caribbean Cruise, a secret police drug raid in February that was aimed at members of a Jamaican religious cult. But Barry said he and Police Chief Maurice T. Turner Jr. have decided not to make the findings public because to do so might jeopardize future secret operations.