Abstract
February 2005 marks the centenary of one of the most important pieces of public health jurisprudence, the US Supreme Court case of Jacobson v Massachusetts, which upheld the authority of states to pass compulsory vaccination laws. The Court's decision articulated the view that the freedom of the individual must sometimes be subordinated to the common welfare. We examined the relationship between the individual and society in 20th-century public health practice and law and the ways that compulsory measures have been used to constrain personal liberty for the sake of protecting the public health.