Mr Case said he had “so far been made aware of fewer than one hundred senior civil servants who hold paid employment alongside their civil service role”.
“They are often providing contributions to wider public life – for example as a magistrate, reservist, school governor or charity trustee,” he said in a letter to a Commons committee.
“I have been heartened to see that colleagues are making a contribution to wider society.”
Mr Case ordered every government department to trawl through their staff’s employment after it was revealed a former head of procurement became a Greensill adviser – while still a civil servant.
Bill Crothers began working for the firm in September 2015, but did not leave his role as chief commercial officer until November that year – a “shocking revelation”, Labour said.
The letter is dated 23 April, the day that Eddie Lister – the prime minister’s longest-standing aide – stood down suddenly as his special envoy to the Gulf.
He was facing criticism of his private sector interests, having remained on the payroll of two property developers throughout his time in No 10.
There was an outcry when Mr Crothers denied any wrongdoing, in working for Greensill, and said such outside roles were “not uncommon”.
Mr Johnson appointed Nigel Boardman, a high-flying lawyer and business department director, to investigate Mr Cameron’s lobbying for Greensill, a collapsed finance firm which employed him.
But the choice has been attacked as “cronyism”, after it emerged Mr Boardman opposed Mr Cameron’s limited curbs to lobbying practices nearly a decade ago.
Meanwhile, Mr Case faced increasing criticism from MPs on the public administration committee for failing to give straight answers on other sleaze controversies, by:
* Refusing to say whether was aware of private donations being used to cover cost of the Downing Street flat renovations
* Suggesting the investigation into the so-called ‘chatty rat’ leak of Covid lockdown plans last October unlikely to be successful, after the passage of time.
* Not ruling out an inquiry into “let the bodies pile high” leak – despite the prime minister insisting it was untrue that he had said the incendiary remark.
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