Sounds like Alien v Predator. Well, the Supreme Court might have taken up that question, but in the event, decided not to get involved with it. My Opinio Juris co-blogger Duncan Hollis explains at OJ. The case handed down today is Samantar v Yousef. I concur with Duncan’s takeaway:
For human rights activists, however, the case had real import for the future of litigation under the Alien Tort Statute (ATS) … My own first take, however, is a simple one, namely, that human rights activists should be breathing a huge sigh of relief tonight. The Court had a chance here to gut the ATS, and it declined to do so.