Bill has been appointed conservator for his mother. His sister, Marge, devised a scheme to steal their dear old mother's savings. Marge presented the plan to Bill, and he agreed to proceed. Bill and Marge went to Mother's bank, and Bill used his status as conservator to gain access to Mother's safe-deposit box. While Marge waited outside the vault with the bank officer, Bill removed all of the money, jewels, and stock certificates in the safe-deposit box. Later the two split the contents. Marge is best described as a(n)