As explained
by the ECJ in its previous case - law (Case C ‑ 419 / 14, WebMindLicenses), the requirement that any limitation on the exercise of that right must be provided for
by law implies that the legal basis which permits any interference with personal rights and
liberties must be sufficiently clear and precise, affording legal protection against any arbitrary interferences
by public authorities.
«Individuals may say or do what they please, provided they do not transgress the substantive law, or infringe the legal rights of others...
public authorities (including the Crown) may do nothing but what they are authorised to do
by some rule of the common law (including the royal prerogative) or statute, and in particular they may not interfere with the
liberties of individuals without statutory
authority.»