Government ministers have been accused of failing to protect whistleblowers despite their role in exposing a series of major scandals.
The Commons Public Accounts Committee said the treatment of whistleblowers was often "shocking," with bullying and harassment from colleagues.
However, government departments were unable to say whether any action had been taken against their persecutors.
The committee highlighted the important role played by whistleblowers in uncovering the scandals at the Mid Staffs NHS hospital trust and policing of the Hillsborough football stadium tragedy.
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