Proportionality principle
A requirement that state action pursuing a legitimate aim must be suitable, necessary, and reasonable in its impact on affected rights or interests.
The proportionality principle is central in Swiss constitutional and administrative law. It asks whether a public measure pursues a legitimate public interest, is suitable to achieve it, is necessary because no milder equally effective measure is available, and remains reasonable when weighed against the burden imposed. The doctrine structures review of restrictions on fundamental rights, police measures, sanctions, planning decisions, and discretionary administration. Comparatively, it is also a major method in European human rights and EU-style public law reasoning.