The assertion was made as the legal challenge to the Brexit which began last week is heard by the High Court.
Attorney General Jeremy Wright said the Prime Minister can use the royal prerogative to take Britain out of the European Union because after the referendum, the executive power is made available to “give effect to the will of the people.”
“This is not a narrow legal challenge…It seeks to invalidate the decision already taken to withdraw from the EU,” said Wright according to The Guardian
The challenge seeks to force the government to be required to have an Act of Parliament authorise the initiation of Article 50.
Under the article, it is decreed that any EU member state may leave the union “in accordance with its own constitutional requirements,” a stipulation vague enough to allow differing interpretations.
The lord chief justice, Lord Thomas of Cwmgiedd, the master of the rolls, Sir Terence Etherton, and Lord Justice Sales are hearing the challenge but given the importance of the matter, the case is expected to make its way all the way up to the Supreme Court before the year’s end.
“Making and unmaking treaties are an established use of royal prerogative powers. The use of prerogative powers [to trigger Brexit] was wholly within the expectation of parliament,” Wright told the senior judges.
“The question is, has parliament acted to limit the availability of the royal prerogative powers? The answer, we say, is no.
“There’s nothing expressed in legislation that [shows] parliament has attempted to circumscribe the powers to make treaties. Parliament has conspicuously refused to legislate on withdrawing from the EU despite many opportunities if it had so wanted.”
Theresa May can legally make Brexit happen by triggering Article 50 of the Lisbon Treaty without an Act of Parliament, the High Court has been told.