Sixsmith is just the latest victim

If there's a cardinal sin in Whitehall, it's not going quietly. Making a fuss and hanging out the departmental washing on a public line is unforgivable in the eyes of the Permanent Secretary. Being found on your desk embracing a blow-up doll of Margaret Thatcher will get you six months' compassionate leave on full pay. But blow the whistle? Not done in Whitehall. Such displays get right up Sir Humphrey's nose. He prides himself he's in charge of a "Rolls-Royce" (as the British Civil Service used to be known). He hates the idea of some overalled oik from the more worldly end of his empire pointing out that there's an oil leak.

That, essentially, is what Martin Sixsmith has done this week. Right or wrong - and I believe the double-dealing and the clumsy attempt to "bounce" him into resigning justifies his going public - the mandarins will not forgive or forget.

I was eased out of the Northern Office on the grounds of "personal chemistry and style" in July 1997 on the orders of - but not directly by - Mo Mowlam. Even though I'd gone, she still bad-mouthed me. I was, variously, "not up to the job", "a w*****", "anally retentive". I was still a civil servant so I held my peace until spring 1998 and then, like Sixsmith, revealed what had happened in The Sunday Times .

The Downing Street media machine is trying to limit the damage of the Sixsmith/Jo Moore affair, suggesting that the spin-doctor problem is a temporary, recent and localised difficulty. It is none of these.

It is not temporary - so long as so many special advisers remain in top posts, at the shoulder of their ministers. The Tories got by with 35 - under New Labour the number is 80, with more than 20 in Downing Street alone.

It is not recent - almost the minute Labour came to power in 1997, the destabilising of established Civil Service press officers started. Within a short time of Mo Mowlam's arrival at the Northern Ireland Office, I was fingered in the press - "Speculation now surrounds the future of Andy Wood, the NIO's redoubtable spin doctor ..."

And it is not localised: in his previous job, Byers tried to exert political pressure on his head of information at the employment and education department. At the Treasury, the highly able information chief Jill Rutter was, in her own words, "left with a quarter of her job" as Ed Balls, the Chancellor's special adviser, and Charlie Whelan, his irrepressible but dangerously amateur media adviser, started extending their spheres of activity. Jill was shrewdly snapped up by BP. At the Department of Social Security, Steve Reardon was labelled "dead meat" by Harriet Harman's special adviser. Blind-sided by Harman's dithering inability to decide whether to take a Cabinet pay rise or not, Steve soon found a new post at the Institute of Directors. (His successor? Martin Sixsmith.)

After I'd gone, things got no better. In 1998, three experienced career press officers - neutral civil servants - were excluded from interviews for the position of head of news at my old department. I protested to permanent secretary Joe Pilling even though I was no longer with the NIO. Their exclusion was "as bizarre as it is indefensible", I wrote. Pilling's reply pooh-poohed such unworthy thought. The post was filled by a Daily Mirror journalist, Sheree Dodd - who, only months before had written a gushing profile of Mo Mowlam.

The truth is as brutal as it is bald: within a couple of years of Tony Blair's 1997 victory at the polls not a single pre-election head of information remained in place in Whitehall.

Eighteen years in opposition had produced a "never again" attitude in New Labour. This time the media would not dismiss them so easily. Reporters would be harried, challenged and bullied. But civil service information officers wouldn't do this - they would, quite rightly, resist turning out party propaganda disguised as supposedly apolitical government press notices. New people - their own people - had to be brought in to do the dirty work. The Government information machine had to change tack - it would be impossible to drive forward the Labour agenda while there were still impartial and non-biddable operators at the helm. So out we went in a mass cull.

Where is this all leading? I suggest the answer is about 3,000 miles west. In Washington DC, every time there's a change of President, about 7,000 public servants are kicked out to make way for a new wave of political appointees. Change the party of government as well as President and that number is doubled. It may do wonders for the Washington furniture removal industry - but it does nothing for continuity of government.

I prefer the British system, whereby the Civil Service is able to provide continuity and professional advice, and to be able to offer a contrasting view without being judged disloyal. The growing gang of media manipulators browbeating government press officers into producing taxpayer-funded party-political propaganda instead of reliable facts and figures are beginning to make this impossible.