Which of the following novelists was not a lawyer before becoming a very successful writer?

David John Moore Cornwell (October 1931–December 2020), known by his pen name John le Carré, was a British-Irish author and best known for creating spy novels. During the 1950s and 60s, he worked for both the British Security Service (MI5) and the Secret Intelligence Service (MI6). His third novel, "The Spy Who Came In from the Cold" (1963), became an international best-seller. It remains one of his best-known novels. During his career, he was able to write 11 George Smiley related novels, the George Smiley collections ("The Incongruous Spy" (1964), containing "Call for the Dead" and "A Murder of Quality" and 'The Quest for Karla" (1982), containing "Tinker Tailor Soldier Spy", "The Honourable Schoolboy", and "Smiley's People". Additionally, le Carré wrote at least 12 standalone novels and 2 Semi-autobiographical works ("The Naïve and Sentimental Lover" (1971) and "A Perfect Spy (1986).

Scott Frederick Turow (b. April 1949 in Chicago, IL), an American author and lawyer, has written 11 fiction and 3 nonfiction books.

Erle Stanley Gardner (July 1889–March 1970, born in Malden, MA) was an American lawyer and author of detective stories. He also published under the pseudonyms A.A. Fair, Kyle Corning, Charles M. Green, Carleton Kendrake, Charles J. Kenny, Les Tillray and Robert Parr.

Richard North Patterson (b. February 1947 in Berkeley, CA) is an American fiction writer, attorney and political commentator. He is known for writing thrilling psychological suspense novels.