Luban, David J. & Henry Shue. "Mental Torture: A Critique of Erasures in U.S. Law." Georgetown Law Journal.
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This is an excellent resource for outlining the problems in operationalizing the definition of torture in U.S. statute, particularly "severe mental pain or suffering." It certainly mirrors the challenge in working with US statute that confounds psychological forms of torture with psychological effects of torture, and it lays out definitional issues that have tremendous implications for how torture survivors are identified, counted, and offered treatment.