What is a statutory declaration, and when do documents need witnessing?
A statutory declaration is a formal written statement of fact, signed before an authorised person, which carries criminal liability if knowingly false — which is what gives it weight in place of sworn evidence in court.
Where they are used: name changes; confirming facts for government applications; declarations of identity or marital status; asserting facts where records are missing; certain company and property matters; and anywhere an organisation requires a formal statement rather than an assertion.
Who can take one: a solicitor, notary, commissioner for oaths, or another authorised person — who must not be connected to the matter, so your own solicitor acting in the case generally cannot take your declaration in it.
What happens. You sign in their presence, they confirm you understand its effect, and they sign and record the place and date. They are not verifying that the contents are true — they are witnessing that you declared them, which is a distinction people frequently misunderstand.
Making a false declaration is an offence, which is precisely the point.
The related documents, which get confused:
An affidavit, sworn on oath or affirmed, used in court proceedings.
A witness statement, containing a statement of truth rather than being sworn — now the usual format in civil proceedings, and dishonesty in one can be contempt of court.
A deed, requiring signature witnessed by an independent person, used where the law demands one — including transfers of land, powers of attorney and documents with no consideration.
A certified copy, where someone confirms a copy is a true likeness of an original.
Notarisation, by a notary public, which is the form generally required for documents being used abroad — frequently followed by an apostille, a government certification confirming the notary's authority, required by countries party to the relevant convention.
Who can witness a signature generally: an adult of sound mind who is not a party and not a beneficiary, physically present, watching the signature happen. Remote witnessing by video is not universally accepted, and requirements vary by document type.
General information, not legal advice.