The principle of proportionality has long been the key mechanism in Europe for deciding whether state action has encroached on human rights. Prior to the UK’s adoption of the Human Rights Act 1998 (HRA), proportionality enjoyed only sparing patronage by UK courts, and then typically only when EU obligations required it. The HRA, however, by making the ECHR enforceable in UK courts, has introduced proportionality into UK public law to a degree some have called irreversible. Recent empirical research has indicated that no other principle has been more important in resolving conflicts between the interests of security and human rights. Proportionality has been the deciding factor in cases involving derogations from the ECHR based on a state of emergency, clashes between ECHR rights, the treatment of immigrants, the wearing of religious apparel, and the rights of parents over frozen embryos. Unfortunately, UK courts receive very little guidance from the European Court of Human Rights on...
