Whistleblowers in the armed forces should be given the same protection as civilian employees, according to a senior SNP MP.
Armed forces personnel are forbidden from discussing their work with MPs, MEPs or members of devolved legislatures (MDLs) such as the Scottish or Welsh parliaments without the approval of UK Government ministers.
SNP defence spokesman Angus Robertson, the party's leader at Westminster, has questioned "what the MoD (Ministry of Defence) has to hide". He insisted that "scandals" such as kit shortages, maintenance shortcuts and "the many MoD procurement bungles" would not have emerged without whistleblowers.
Mr Robertson has circulated MoD instructions on contact with parliamentarians, obtained through a freedom of information request, informing forces personnel they are "accountable to ministers" and "not accountable to Parliament".
The document is marked "unclassified" but with instructions that it is "not to be communicated to anyone outside HM Service without authority". It says there should "be no need for contact between Crown servants, irrespective of seniority, and parliamentarians unless specifically authorised by the Secretary of State or a delegated minister".
Personnel are also instructed to inform ministers of any unexpected or unsolicited contact with parliamentarians or their staff. UK Government guidance says employers cannot prevent employees from reporting improper, illegal or negligent behaviour as part of their employment contract or any other agreement.
Mr Robertson, whose Moray constituency covers RAF Lossiemouth and Kinloss barracks, has questioned why this does not appear to apply to MoD staff.
He said: "I am appalled by this diktat which raises the obvious question of what the MoD has to hide. It is totally unacceptable for anyone to dictate what an individual can tell their MP - particularly given our dual duty to represent constituents and hold the Government, including the Ministry of Defence, to account."
An MoD spokesman said MPs have privileged access to defence ministers in Parliament.
He said: "MPs and peers have direct privileged access to ministers and any information they require from the department is provided by ministers, for example in answer to parliamentary questions. It is important that information provided to parliamentarians is coherent and reflects agreed final decisions which have been made by MoD ministers."