Christie was admitted to the bar in New York in 1957 and in the District of Columbia in 1958. He spent two years in private practice in Washington D.C. and from 1960-1961 he was a Ford Fellow at Harvard Law School. From 1961-1962 he was a Fulbright Scholar at Cambridge University. Following his time at Cambridge he became a member of the faculty at University of Minnesota Law School. In 1966 he left the University of Minnesota and returned to Washington D.C. where he served as the Assistant General Counsel for the Near East and South Asia of the Agency for International Development.[5]
He has been on the faculty of Duke University School of Law since 1967.
Christie influenced the Duke University academic governance through the so-called Christie Rule, recommended by a committee he was chairing in 1972. The rule aims to guarantee that the voice of the faculty be heard prior to the Board of Trustees reaching significant decisions.[6]