A Chevy Chase psychiatrist who speculated to a reporter about the possible suicide motives of his patient, former CIA official John A. Paisley, is now under investigation by the ethics committee of the Washington Psychiatric Society.

The nine-member committee, which deliberates in secret, began investigating Dr. Jack Baruch one week ago after receiving a formal written complaint from a local psychiatrist, according to Virginia Price, executive secretary of the 1,000-member society.

Action by the committee could ultimately result in Baruch's dismissal from the professional association and possible action by the Maryland Board of Medical Examiners, the state's licensing board. Lesser penalties could include suspension, censure or admonishment by the society. Dr. Howard Kaiser, a committee member said.

Baruch refused to comment yesterday when asked about the investigation.

Paisley's body was found Oct. 1 floating in the Chesapeake Bay with a bullet wound in his head. His death was listed a "probable" suicide last week by Maryland State Police, but the Senate Intelligence also is conducting an inquiry into his death because of his CIA connections.

In speculating on the causes of Paisley's death, Baruch had said that a recent forced separation from a woman friend might have triggered "feelings of loss or abandonment" by his patient who, Baruch said at one point "very well could have been a candidate for suicide."