In a brief speech before Parliament was adjourned, Mr Mah noted that the privilege of parliamentary immunity enjoyed by MPs must be balanced by high standards of accuracy.

MPs had a duty not to criticise any person or body, 'unless they are satisfied that these criticisms have a basis', he said.

Under Parliament rules, the Leader of the House is responsible for arranging Government business in Parliament, and will advise the House on the action to take if a difficulty arises, say, if an MP should break certain House rules.

On Wednesday, Mr Sin Boon Ann (Tampines GRC) criticised The Straits Times for its reporting of the Aware saga, citing an e-mail he had received from a person he said he did not know.

He said he had not verified the substance of the e-mail, but 'would not be surprised if it were true and would be very concerned if it is'.

He apologised to the House and 'all those involved' the next day, noting that the privilege of free speech in the House imposed higher standards of diligence on MPs.

Mr Mah noted that MPs were entitled to 'be forthright and to make forceful comments', as the law accords them the privilege of freedom of speech and immunity from civil or criminal proceedings for statements they make in Parliament.

This is so that debate in Parliament can be free and uninhibited, and the House can perform its functions without fear or favour. But he reminded members that 'such a privilege should be exercised responsibly in the public interest'.

'If members wish to rely on third-person reports or hearsay, they should first take steps to verify the identity of the authors and the accuracy of the statements. Members should not rely on such statements if they have not verified them. Not even if they so inform the House,' he stressed.

Read the full report in Saturday's edition of The Straits Times.