Jeremy Sugarman1,2, Roger A Barker3, R Alta Charo4,5. 1. Berman Institute of Bioethics, Johns Hopkins University School of Medicine, Baltimore, Maryland. 2. Johns Hopkins University Bloomberg School of Public Health, Baltimore, Maryland. 3. WT-MRC Cambridge Stem Cell Institute, Department of Clinical Neuroscience, University of Cambridge, Cambridge, England. 4. University of Wisconsin Law School, Madison. 5. Stanford Center for Advanced Studies in Behavioral Sciences, Stanford University, Palo Alto, California.