In May 2009 , Souter wrote President Barack Obama and said he planned to retire later in the same year .
The election of a Democratic president in 2008 made Souter more inclined to retire , but he did not want to create a situation in which there would be multiple vacancies at once . Souter apparently became satisfied that no other justices planned to retire at the end of the Supreme Court 's term in June 2009 .