Investigating the illegal wiretapping of a Law School professor's office phone, officials there said yesterday that they have no record of anyone breaking into his office building in recent months and that the tap could have been installed easily during working hours.

Administrators said that the phone of Tyler Professor of Constitutional Law Laurence H. Tribe '62 could have been tapped while people were in the building since people walk in and out of Griswold Hall, where his office is located, throughout the day.

Law School security officials said there was no evidence of either a break-in or reports of suspicious individuals in the building during the last eight months, which telecommunications experts say is the period during which the tap was placed.

Harvard officials last week discovered the tap on the line leading from Tribe's office phone, after his secretaries called University police saying they heard strange noises during their phone conversations.

Located in a set of cabinets, the phone lines are now only distinguished from the neighboring supply cabinets by new padlocks and chains on the doors.

To avoid the possibility of future phone tampering, the University will install new doors on the lockers and increase the frequency of security sweeps, Law School officials said.

Griswold contains the offices of high-profileLaw School faculty members such as Alan M.Dershowitz and Tribe, who played a key role informulating the Senate Judiciary Committee'sstrategy to defeat Supreme Court nominee JudgeRobert H. Bork.

Peter Smith, a spokesman for the JudiciaryCommittee, said yesterday that there have been "noindications" that other strategists' phones hadbeen tapped, and that the committee did not planto launch its own investigation. He added that thecommittee is not equipped to conduct such a probe.

The Boston bureau of the FBI, the MassachusettsAttorney General's office and the UniversityPolice are investigating the wiretapping, which isa federal offense.

Tribe's attorney Philip Lacovara, who served asan adviser during the Watergate hearings, saidyesterday that he would pursue leads throughsources in the Executive and Legislative branches.

Lacovara added that Tribe has been involved inseveral controversial issues other than the Borkhearings. "Professor Tribe is involved in a largenumber of issues of public policy. We want toexplore each of those to see which if any of hisopponents were motivated to do this," Lacovarasaid. In addition to his role in the Borkhearings, Tribe served as counsel to Pennzoilwhich won a $10 billion case from Texaco in April.

Lacovara said that he saw no problem with theFBI handling the investigation, and expected thatthey would do an effective job. "If the governmentwas involved in a cover up, we will be able tolearn that, so I fell confident asking the FBI toinvestigate the occurrence of a federal offense,"Lacovara said