This week's confirmation that NHS Scotland chief executive Geoff Scaife is leaving puts the health service in an extraordinary position: no fewer than three of the four chief executive posts are now vacant.

As English ministers prepare to launch their 'national' plan for the NHS - and Scottish, Welsh and Northern Irish ministers mull over similar issues - the health service is effectively leaderless. What an opportunity for ministers to remould the service at the highest levels. What a temptation.

Mr Scaife has been treated with remarkable callousness. 'News' of his departure has been circulating since May, and when he failed to depart quickly enough something akin to a whispering campaign was mounted against him. Last week he was rather obviously left off the NHS modernisation board for Scotland. This week it has been announced that he is leaving two months early without so much as a face-saving sinecure to explain the rush.

Mr Scaife is not alone. A month ago, Scottish health minister Susan Deacon let it be known that she was planning a 'purge' of trust and health board chairs. Two chairs from Tayside have already gone - preceded by widespread and accurate press reports about their future, or lack of it. Another wave may be about to follow.

Before devolution, Scotland's health service was a small, tightly knit world presided over by a powerful executive subject to relatively little political interference. Scandals that have erupted over the past few years suggest this had some unfortunate effects. Too many have revolved around arrogant, bullying and even corrupt cliques. Politicians in the devolved Parliament have rightly condemned this culture. But the experience of Mr Scaife and others suggests the condemnation is only spin deep. Perhaps this is not surprising, given the way the present administration is evolving.

Ms Deacon has faced her own share of briefings and counter-briefings over the past fortnight as the extraordinary story of whether unspent NHS cash should be used for planting trees has unfolded. But it would be better if Ms Deacon now reined back the off-the-record briefers and accepted that the NHS needs leaders who can stand aside from the political backbiting and ensure that the service delivers.

There are persistent rumours that the name of Mr Scaife's successor is already known. But open advertisement, a transparent appointment process and the emergence of a widely respected candidate are the way to overturn Scotland's culture of fear and cronyism. Anything else will entrench it further.