Jerry Johnson, a CIA lawyer, today testified that he did not tell a police detective that the agency would disclaim any involvement with former Green Beret Eugene A. Tafoya, even if the disclaimer were untrue.

Tafoya, who is charged with attempting to murder a Libyan student, claims he shot Faisal Zagallai in self-defense when Zagallai attacked him Oct. 14, 1980, while Tafoya was delivering what he believed to be a CIA message to Zagallai.

On Monday, however, a CIA records custodian denied that Tafoya had ever worked for the agency.

Fort Collins police Det. Ray Martinez had reported that Johnson, an attorney with the CIA's Office of General Counsel, told him last July 16 that the CIA would not acknowledge involvement with Tafoya even if he had been working for the agency.

"I discussed with Jerry Johnson the possibility that if the CIA did hire Tafoya what would their position be in court," Martinez wrote in a report. "Jerry Johnson stated 'We would have to deny any involvement.' "

Johnson testified today that Martinez "misinterpreted" his remarks. Johnson said he told Martinez that the CIA would not be able to disclose classified information but that since Tafoya was not employed by the CIA, no classified information was at stake if CIA employes were asked to testify.

Despite the CIA's denial of having anything to do with Tafoya, defense attorneys were pleased by the testimony of Johnson and George Marling, records custodian for the agency's clandestine services division.

"The fact they admitted the CIA has a policy of denying association with incidents the agency would prefer to keep secret can only help Tafoya," said a source close to the defense.

Tafoya's lawyers also felt that Johnson's testimony cast doubt on the credibility of Martinez, chief investigator in the case.

Martinez testified that Tafoya admitted last May and again in September that he was not sure whether he was working for the CIA when he went to Zagallai's apartment under the pretext of interviewing Zagallai for a job.

Martinez said Tafoya told him he was sent to "rough up" Zagallai as a warning to stop organizing Libyan students in the United States who oppose the government of Col. Muammar Qaddafi.

The prosecution has tried to link Tafoya to Edwin P. Wilson, a former CIA agent who has been indicted for illegally shipping explosives to Libya and who investigators suspect hired Tafoya to assassinate opponents of Qaddafi.

Tafoya has admitted working for Wilson as a courier but claimed that job was a cover for his CIA work.

Testimony concluded today, with closing arguments and jury instructions due Wednesday. The jury is expected to begin deliberations Thursday.