When justices take themselves out of cases they rarely offer an explanation, but it is often not hard to figure out why, or at least make an educated guess.
Financial holdings, revealed in annual disclosure reports, often make clear the reason for justices' withdrawals. In the case of Elena Kagan, her prior job in the Justice Department caused her to sit out the fight over affirmative action in higher education among dozens of other cases since joining the court in 2010.
But Alito did not own either Chevron or telecommunications stock last year, the latest period for which information is available. In addition, neither case came from the federal appeals court in Philadelphia where he was a judge before coming to Washington in 2006, so his recusal would not have been based on previously participating in the case.
And Alito declined to say why he didn't take part in either case, when asked through the court's public information office.
The justices are under no obligation to explain themselves, and most often, they do not.
Last month, the New York City Bar Association issued a report calling on justices to explain their decisions to withdraw from cases as well as their intention to hear cases in which questions have been raised about their ability to be impartial. Kagan and Justice Clarence Thomas ignored calls to sit out last term's health care cases.
Legislation introduced by Rep. Chris Murphy, D-Conn., to accomplish disclosures like the bar association advocated has languished without a hearing since its introduction in March 2011.
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