Gary Walker has long wanted to speak out about what happened when he lost his job in the NHS. But he had signed a “super gag”, and with family to feed and the fear of where his next job would come from, he felt he had no option but to stay quiet.

Mr Walker was chief executive of the United Lincolnshire Hospitals Trust but was sacked for gross professional misconduct after he allegedly swore in a meeting.

He says it was because he wanted to abandon the 18-week target for non-emergency cases as the demand for hospital beds in 2008 and 2009 became desperate.

I have spoken at length to a former colleague of Mr Walker’s, who himself resigned over what happened and who has backed the claims he has made. But we could not report the story because of the order.

And therein lies the problem with these confidentiality clauses which are all too common in the NHS.

Despite promises made by successive secretaries of state for health, they are used to silence legitimate whistleblowers. With a family to support, it takes a strong person to either refuse to sign or to break the order.

Indeed, no sooner did Mr Walker speak to the BBC Today programme than he was contacted by solicitors representing the trust saying it was a clear breach of the agreement and that they would be entitled to recover any payments made under the agreement.

It would seem that Mr Walker was finally emboldened because of the Robert Francis QC Inquiry report which demanded that the confidentiality clauses be banned.

Dr Kim Holt was a paediatrician who, with three colleagues, warned management of problems, including understaffing and poor record-keeping, at the hospital where Baby P was treated just before he died.

Dr Holt claimed that bosses ignored her warnings and removed her from the clinic. They subsequently issued a joint apology with Haringey Primary Care Trust.

But Dr Holt’s experiences led her, with others, to set up Patients First in order to campaign for the NHS to become open and accountable. They have a growing number of examples of NHS employees being bullied, harassed or victimised by raising concerns that involve patient safety.

Update: 1930
Now the Chair of the Health Committee, Stephen Dorrell, has intervened in the row.

In a letter to the Health Secretary Jeremy Hunt, Mr Dorrell said that the committee was “concerned and disappointed to hear that Mr Walker had received a lawyers’ letter which he has interpreted as reinforcing the constraints upon him under the terms of the ‘gagging clause’ in his compromise agreement.”

Mr Dorrell said that normally the committee is reluctant to be drawn into disputes between individual NHS employers and their employees. But he said they felt the need to write in light of assurances received by the Committee in December 2011 from the Department of Health that gagging clauses are inconsistent with the Public Interest Disclosure Act and following the Francis Inquiry.

Mr Dorrell said they would be writing to Mr Walker asking him to set out what lay behind the breakdown of his relationship with the trust.

And he has asked Mr Hunt to confirm that neither the Trust nor any other NHS body will seek to enforce any clause in Mr Walker’s compromise agreement which would impinge on his capacity to respond fully to the Committee’s request.

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Read more: Can you be an NHS whistleblower without being sacked?