Jack Straw has provoked accusations that Government whips are actively encouraging MPs to exempt Parliament from the Freedon of Information Act.
Despite the Government's official stance of neutrality, the Commons Leader has given tacit backing to a private members' bill that would prevent journalists using the right-to-know law to examine MPs' correspondence sent to public bodies on behalf of constituents.
Maurice Frankel of the Campaign for Freedom of Information claims that constituency correspondence is already protected by the Data Protection Act.
But Straw has intervened in the controversy over the Freedom of Information (Amendment) Bill – introduced by former Tory whip David Maclean – to suggest that actions by journalists and Information Commissioner Richard Thomas have put their private correspondance in jeopardy.
"It is all very well for some people to say that there are exemptions, but the truth is that the way that some journalists and the Information Commissioner are acting means that that intention is not being met in practice," Straw has told MPs.
Labour MP David Winnick complained that Government and Opposition whips were "actively encouraging" MPs to back the bill.
When the bill was last considered, on 20 Apri, 25 members of the Government, including culture secretary Tessa Jowell and constitutional affairs minister Bridget Prentice, joined Maclean in the voting lobby.
The two-clause bill has already been given an unopposed Second Reading – when Government whips did not raise their usual objection to private members' legislation – and was approved in a morning by a cross-party committee of MPs.
Straw has told MPs that publication of their correspondence "would drive a coach and horses through the relationship that we have with correspondents".
Winnick said: "If the bill is carried – and it probably will be, because of the active canvassing – Parliament will be accused of hypocrisy and rightly so."
The Freedom of Information (Amendment) Bill was due to go before the Commons on Friday.