A Pentagon committee that reviewed the code of conduct for prisoners of war said yesterday charges of collaboration with the enemy in future wars should be investigated and punished under military law.

Documents released with the committee's report indicated that dismissal of charges against nine Vietnam POW's may have been prompted in part by concern about bad publicity - such as that received in connection with the Myla massacre and Green Beret murder case.

The committee of four civilian Pentagon and seven military officers, including three former POWs, interviewed 50 persons last year, including tow returnees who were charged with collaboration.

The committee suggested only one minor change in wording of the code of conduct, which is designed to give captured American servicemen guidelines for behavior. But the panel recommended that servicement get better training about it.

"All servicemen should learn that their behavior in captivity or detention is fully accountable under U.S. law," the report said. "Further, the committee recommends misconduct in such status should be subject of discriplinary proceedings, upon the return to United States control, of POWs who are believed to have violated the uniform code of military justice."

A summary of an interview with Rear Adm. H. B. Robertson, the Navy's chief legal officer, said the military services had consulted with each other under Defense Department guidance about what to do with accused collaborators. It attributed the outcome partly to "a strong predisposition on the part of the Army that these would be no trials.

"Three things led to this," the summary said. "1. The Mylai experience. 2. The Green Berets case and 3. (Army Chief of Staff Creighton) Abrams' conviction that the POWs should not be subjected to any further confinement."