avid Cameron is, we are told, very embarrassed. But shame might seem a more fitting emotion for an ex-prime minister caught trying to wheedle private favours from former underlings on behalf of a company from which he personally stood to make a fortune. No wonder he spent a month ducking questions about his work for the failed financier Lex Greensill, which will now be subject to an inquiry led by the Cabinet Office. Only on Sunday did Cameron eventually concede that, on reflection, he should have lobbied government on behalf of his new boss via “only the most formal of channels” – rather than going over officials’ heads to text Rishi Sunak or meet Matt Hancock for a private drink. Coming from someone who was himself accused of running an overly casual “chumocracy” when in power, that might seem a bit rich. But it does suggest a dawning realisation that Cameron is no longer merely embarrassed, but potentially embarrassing to his successors. This government is little more than a year old but already mired in sleaze: if it’s not the furore over Covid contracts for ministerial mates, then it’s the ghosts of Boris Johnson’s affair with the entrepreneur Jennifer Arcuri, who roped her lover, the then London mayor, into events promoting her tech career which hadn’t been cleared by his office. The last thing the Johnson administration needs is another cronyism scandal – which perhaps helps to explain why Cameron stressed in his statement that his efforts didn’t ultimately get Greensill Capital (which collapsed last month) very far. Yet those scandals will keep coming so long as Tories keep treating Whitehall processes – designed to protect the public interest – as technicalities at best, and ideological foes at worst. Since Dominic Cummings quit, there’s been little talk of the “hard rain” he once supposedly vowed would fall on civil servants. But the itch to politicise an independent and neutral Whitehall long predates the former No 10 adviser. For Tories it’s rooted in a knee-jerk loathing for anything smacking of bureaucracy or lack of can-do spirit – which may only intensify as promises made over Brexit collide with what civil servants are forced to explain is the reality. This scandal shows just why a Whitehall free from political interference matters, and why we allow civil servants to be bypassed, undermined or otherwise bullied into submission at our peril. Where Cameron’s efforts failed, it was mostly thanks to civil servants doing what they exist to do, and focusing on the public interest. When Greensill Capital’s efforts to climb aboard a Treasury scheme for keeping businesses afloat through the pandemic were rejected, Cameron’s texts to Sunak seemingly won a lifeline most companies could only dream of: the chancellor said he had “pushed” civil servants to see if something could be made to work. But if Sunak did, then it seems Treasury officials pushed back, confirming their original decision to exclude the company. Something similar seems to have happened years earlier, when Cameron was himself in Downing Street and the then head of the civil service, Jeremy Heywood, first brought his former City colleague, Greensill, into Whitehall (to develop ideas for speeding up government payments to suppliers). According to the Sunday Times, despite the late Heywood’s patronage, officials in several departments were wary of Greensill’s efforts to insert himself into their supply chains, and rebuffed his ideas. Cameron arguably had better luck with Hancock, securing introductions for Greensill to senior NHS executives so that the banker could pitch his payroll app, Earnd, which was later adopted by some individual trusts as part of a pilot scheme. But where Greensill was rebuffed, each time the antidote to his charm seems to have been plain old due process, or sceptical civil servants niggling methodically away at details glossed over in the sales pitch. That process can be grindingly slow, pedantic and sometimes doubtless over-cautious. Not all wisdom resides in Whitehall, and sometimes lobbying can be a means of bringing bright ideas to ministerial attention. But civil servants can only separate the odd grain of wheat from the mountains of self-interested chaff if they’re free to scrutinise without political fear or favour. For politicians who rage against the machine, the lesson of this scandal is just how often they’d make fools of us all without it. Gaby Hinsliff is a Guardian columnist