Section 6(1)(a) of the Statistics and Registration Service Act 2007 (c. 18) (“the Act”) provides that statistics produced by the Statistics Board, a government department, the Scottish Administration, a Welsh ministerial authority, a Northern Ireland department, or any other person acting on behalf of the Crown are official statistics. Section 6(1)(b) of the Act provides that such other statistics as may be specified by order by a Minister of the Crown, the Scottish Ministers, the Welsh Ministers or a Northern Ireland department are also official statistics.
Link: The Official Statistics Order 2018
Source: Legislation .gov.uk
