<P> The table below ranks all United States Supreme Court Justices by time in office . The basis of the ranking is the difference between dates; if counted by number of calendar days all the figures would be one greater, with the exception of Charles Evans Hughes and John Rutledge, who would receive two days each . </P> <P> The length of incumbency for the five individuals confirmed for associate justice, and later confirmed for chief justice separately--Charles Evans Hughes, William Rehnquist, John Rutledge, Harlan F. Stone, and Edward Douglass White--measures their cumulative length of service on the Court . A nominee who was confirmed by the United States Senate but declined to serve, such as Robert H. Harrison, or who died before taking his seat, such as Edwin M. Stanton, is not considered to have served as a Justice . Such individuals are not included . The start date given for each justice is the day he or she took the oath of office, with the end date being the date of the justice's death, resignation, or retirement . A highlighted row indicates justice currently serving on the Court . </P> <Table> <Tr> <Td_colspan="2"> Longest Supreme Court tenure </Td> </Tr> <Tr> <Td> William O. Douglas 13,358 days (1939--1975) </Td> <Td> Stephen Johnson Field 12,614 days (1863--1897) </Td> </Tr> <Tr> <Td_colspan="2"> </Td> </Tr> <Tr> <Td_colspan="2"> Shortest Supreme Court tenure </Td> </Tr> <Tr> <Td> James F. Byrnes 452 days (1941--1942) </Td> <Td> Thomas Johnson 163 days (1792--1793) </Td> </Tr> </Table> <Tr> <Td_colspan="2"> Longest Supreme Court tenure </Td> </Tr>

Who was the longest serving supreme court justice