Knox’s clerkship ended when McReynolds fired him for taking time off to sit for the Washington, D.C. bar examination, which Knox failed. The remainder of his life was a succession of personal and professional disappointments. He returned to Illinois in 1937. He initially landed, from 1938 to 1942, a position with a prestigious Chicago law firm (Loesch, Scofield, Loesch & Burke) but was fired when he failed the Illinois bar examination. Although Knox finally passed the exam (on his third attempt), he never acquired a secure and permanent position with a firm. From 1942 to 1945, he worked as Senior Attorney, U.S. War Production Board, Region VI, and from 1945 to early 1947 at the Cravath law firm in New York City. An attempt at running his family's already faltering mail-order book business after his father's death proved disastrous, but Knox eventually found his niche in the Chicago claims office of the Allstate Insurance Company, a Sears subsidiary, working there until his retirement in 1973.
