The justices must decide whether a law known as the Alien Tort Statute permits US courts to rule on that case.

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In that case, he is accused of being an illegal alien, possessing four firearms and false identity documents.

BBC: Eddie Maher

The court heard arguments in February, only to kick the case back with a crucial question: Does the Alien Tort Statute allow such lawsuits at all?

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Although the killing occurred in Colombia, the lawsuit argues that U.S. federal laws -- including the Alien Tort Statute and the Racketeer Influenced and Corrupt Organizations Act -- give American courts jurisdiction in the case.

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