Jim Downey is one of the most long-standing writers of Saturday Night Live, from 1976 to 2013; he served as head writer from season 12 to season 20. He is the brother of Robert Downey, Sr., and uncle of Robert Downey, Jr..
Downey joined SNL for season 3, and was one of several writers promoted to the new featured players cast category when it was created for season 5. When Lorne Michaels quit as producer at the end of that season, Downey left as well, and shortly thereafter became head writer for Late Night with David Letterman when the show was created. He returned to SNL a few years later, during the Dick Ebersol years (and can be seen in the sketch "White Like Eddie", from Eddie Murphy's hosting gig in season 10.) When Lorne Michaels returned to SNL in season 11, Downey was promoted to head writer.
He was eventually forced out has head writer with the massive cast changeover following season 20, but remained, credited as "Weekend Update Producer" and writing exclusively for Norm MacDonald's Weekend Update. When MacDonald was forced off Update in season 23, Downey was fired; he has later recounted in interviews being told of his firing at the same time he was informed of the death of Chris Farley. He returned in 2000, and (aside from a break in 2005 to act in the movie There Will Be Blood) remained at SNL until retiring after season 38, though much of his writing in his last few years was done at home. During his time on SNL, he was often seen in cameos and voiceovers.