Firstly, the government should not permit parents to put their children at avoidable risks of death and suffering, and has an overriding duty to protect children from these outcomes, when doing so is easy and safe. Secondly, the government should guard the common good of herd immunity in society, in order to protect vulnerable persons who cannot protect themselves for medical reasons. First, mandatory vaccination supersedes the parental freedom of religion and conscience; second, an unqualified obligation is compatible with the legal principle of proportionality. Section five discusses and refutes the pragmatic objection that mandatory vaccination might backfire in the protection of herd immunity. After having discussed these possible legal
