The Attorney-General has rebutted claims the post-handover courts will not have jurisdiction to decide on the legality of the provisional legislature.
In a letter to the South China Morning Post published today, Mr Mathews said the claim by SAR executive councillor Sir Sze-yuen Chung was seriously flawed.
Sir Sze-yuen had said under Article 19 of the Basic Law it was up to the central Government to decide if an act is an 'act of state'.
But Mr Mathews points out that Article 19 provides for the chief executive to obtain a certifying document from the central Government in respect of questions of fact concerning acts of state.
'For example, such a document could set out what the National People's Congress had decided in respect of the provisional legislature.
'However, the question whether an act is or is not an act of state is a question of law, which the courts must decide,' he writes. 'As a general rule . . . it will be for the courts of the SAR to determine whether an act is or is not an act of state.' Challenges to the legality of the provisional legislature did not relate to 'acts of state'.