Elena Kagan (b. 1960) is the junior Associate Justice of the Supreme Court of the United States, who took her seat in August 2010. Previously, she was U.S. Solicitor General, to which she was also appointed by President Barack Obama.
Her primary background is academic law, having been professor and then dean at Harvard Law School. Before that she had served as a clerk to Justice Thurgood Marshall in 1987-1988. She has no direct experience as a judge.
Since, as Solicitor General, she either directly argued or supervised the arguing of U.S. government positions before the Supreme Court, she has had to recuse herself from a good many cases in the court queue, since she had worked on them. Recently, she was the lead government attorney on Citizens United v. Federal Election Commission.