Revelations of a former NHS chief executive who was legally "gagged" and now faces the loss of his pay-off for speaking out about worries over patient safety would be a cause for concern at any time. Coming, as it does, barely a week after the Francis report into the Mid Staffordshire scandal, it is more poignant still.

The inquiry led by Robert Francis QC described horrific levels of neglect at the hospital between 2005 and 2009, leading to as many as 1,200 deaths. And among his 300 recommendations, Mr Francis stressed the need for a statutory "duty of candour" requiring NHS staff to be open about mistakes.

For Gary Walker, who was dismissed from the United Lincolnshire Hospitals Trust – one of 14 NHS organisations having its persistently high death rates investigated – such a proposal is ironic, indeed. The former manager has now broken the non-disclosure agreement signed as part of his pay-off, detailing his alarm that targets appeared to be more of a priority than patients – and faces the loss of his £500,000 severance deal as a result.

It is unforgivable that Mr Walker's fears did not come to light in 2010, when he left his job, so they could be immediately disproved or remedied. There is but one conclusion here. The imposition of gagging orders on state employees working in areas of public safety cannot be justified. Not only must Mr Walker's immunity be guaranteed. His case must signal an end to a practice so wholly contrary to the public interest.