The members of the public who lodged the complaint which led to the departure of former council leader Derrick Murphy from Norfolk County Council have urged whoever takes his place to change the culture at County Hall.

Seven people – John Martin, Ron Cornell, Jenny Perryman, Joy Franklin, Christine Hall, Mark Russell and Stuart Wilkie – lodged a complaint about Mr Murphy's behaviour last summer.

They did so after the conclusion of an independent investigation into an email which was sent to BBC Radio Norfolk by Kevin Vaughan, the political assistant to the Conservative group at County Hall, last April.

It concluded that email was sent on the wishes of then council leader Derrick Murphy, which led to the seven making a complaint about Mr Murphy's behaviour.

That led to another independent investigation, carried out by Jenni Richards, QC, She recommended Mr Murphy had breached the council's code of conduct four times and he was brought before a standards committee last Friday.

It emerged at that hearing that the council's chief executive, David White, had secretly recorded a conversation he had with Mr Murphy over the email on April 27 last year. Mr White told the hearing, in his view, Mr Murphy had tried to lay the blame for the email at Mr Vaughan's door.

Ms Richards had recommended that the committee should find Mr Murphy had twice breached the code of conduct because of misleading and evasive answers to Mr White.

But the committee did not find Mr Murphy had breached the code of conduct on that matter. However it did find he breached the council's code of conduct in asking Mr Vaughan to claim it was not Mr Murphy, but twin-hatted councillors [on the county and West Norfolk Council] who requested him to send it.

Mr Murphy has since quit as chairman and leader of the Conservative group and has announced he will not stand as a councillor in May. A leadership contest is under way.

Retired solicitor John Martin explained why he and the others lodged the complaints.

He said: 'The origin of the seven conduct complaints lies very much in the failure of the chief executive at the end of last May to instigate a separate external investigation. Given our concerns at that, we had little alternative but to go this route. I have now submitted a corporate complaint against the council in respect of that failure.

'We have always been at pains to make it clear that these conduct complaints were not politically motivated, nor did they have anything to do with the proposed Saddlebow waste incinerator project.

'What we do have in common is a long-running concern that for some time now there has been a culture in County Hall that is not consistent with principles of honesty, integrity, accountability and transparency. Clearly, the next leader of the council needs to take urgent steps to bring about a change in that culture.'

When asked why Mr White did not order an investigation into Mr Murphy's behaviour, a council spokesman said: 'It was the independent internal investigation that concluded the political assistant had been acting on Derrick Murphy's wishes in sending the email to BBC Radio Norfolk.

'The chief executive was not involved in that investigation and was deliberately distanced from it in case he needed to hear any appeal.

'Almost immediately following publication of the results, the authority received complaints from others that swiftly triggered the QC's investigation.'