John Bercow, right, accepted the donations to help him hold on to his parliamentary seat in Buckingham

This article is subject to a legal complaint by Mr Bercow.

John Bercow stopped the Commons being warned about police inquiries into Keith Vaz after accepting tens of thousands of pounds from the MP’s associates.

The Speaker, who is required to be scrupulously fair as chairman of the lower house, took the gifts to help him to hold on to his parliamentary seat at the general elections in 2010 and 2015.

The Times used the Freedom of Information Act to request details of all Mr Vaz’s communications with the Speaker’s office but Mr Bercow forbade any material to be disclosed. He signed a formal certificate presented to Elizabeth Denham, the UK’s information commissioner, saying that to hand anything over would “prejudice the effective conduct of