 The U.S. Congress established the National Commission for the Protection of Human Subjects of Biomedical and Behavioral Research (1974–78), charged with formulating regulations governing the use of humans in research.Jonsen was a Commissioner and participated in development of regulations regarding use of the human fetus, children and mentally incapacitated persons as research subjects; he also assisted in the writing of the Belmont Report, the statement of ethical principles that has become the leading statement on research ethics.In 1979, Jonsen was appointed to the successor body, the President's Commission on the Study of Ethical Problems in Medicine (1979–82) which devised reports on brain death, foregoing life-support, informed consent and other topics that have become the main subjects of bioethics.