Mr. Garner, a lifelong Democrat who was active in behalf of civil rights and environmental causes, always said he met his wife, the former Lois Clarke, in 1956 at a presidential campaign rally for Adlai Stevenson, though in “The Garner Files” Mrs. Garner said they had actually met at a party earlier. She survives him, as do their daughter, Greta, known as Gigi; and Mrs. Garner’s daughter from a previous marriage, Kimberly.