The Justices who dissented argued that Government could use its prerogative powers to exit the European Union without consulting Parliament first.
Lord Reed, Lord Carnwath and Lord Hughes stated that the 1972 European Communities Act (ECA) did not affect Government's prerogative powers to trigger the Brexit process as the ECA is "inherently conditional on the UK's membership of the EU."
The argument in the judgment summary reads: "The ECA does not impose any requirement or manifest any intention in respect of the UK's membership of the EU. It does not therefore affect the Crown's exercise of prerogative powers in respect of UK membership."
The three Justices who voted against the Supreme's Court Article 50 ruling: