The country's most senior civil servant will be cross-examined by MPs investigating the Andrew Mitchell "Plebgate" affair. Sir Jeremy Heywood will be asked about his role in finding out what really happened at the Downing Street gates.
The Sutton Coldfield MP was forced to resign as Chief Whip but has always denied calling police officers "plebs".
A report out today says David Cameron brought in the the wrong person to investigate 'Plebgate'.
Andrew Mitchell has written a piece in which he has accused the police of trying to destroy his career in a smear campaign.
A police officer who claimed to have witnessed Andrew Mitchell's 'rant' at Downing Street is being investigated by the police watchdog.