Nullity of administrative act
A severe defect that makes an administrative act legally ineffective from the outset and disregarded by any authority.
Nullity is exceptional in Swiss administrative law. An act is treated as void only where the defect is especially grave, obvious or readily recognisable, and legal certainty does not require treating it as valid. Typical examples may involve lack of subject-matter competence or an impossible content, but the assessment is strict and fact-specific. Unlike a merely unlawful decision, a null act produces no binding legal effects and its invalidity may be invoked even outside ordinary appeal periods.