Last week, it emerged that a report to Northumberland County Council's audit committee said an independent investigation had uncovered "inappropriate" conduct at the authority in relation to the handling of an application for the Dissington Garden Village scheme on the edge of Ponteland.
The report, by chief executive Daljit Lally, said that an investigation into a whistleblowing complaint had revealed that "conduct in relation to that planning application [was] not transparent or appropriate".
A spokesperson for the Royal Town Planning Institute confirmed that it had received a complaint from the council about an RTPI member that it is "currently investigating".
"We take all complaints seriously and have a rigorous investigation process in place which we will follow," the spokesperson said.
The institute’s code of professional conduct sets out five core principles of standards, ethics and professional behaviour expected of its members.
Lally’s report said that the investigation had revealed that "conduct in relation to that planning application [was] not transparent or appropriate".
It added: "It appears that significant efforts were made by several persons in positions of authority and control within the county council to collude with and secure a number of inappropriate advantages for the planning applicant/developer in the application in question.
"Such advantages would not be conferred on any other planning applicant in the normal conduct of the authority’s planning functions."
The report said that planning officers recommended approval for the application, even though subsequent advice from the Planning Officers Society, which represents public sector planners, indicated "almost certainly" that "any reasonable planning authority would have recommended the planning application in question for refusal".
The report said that the investigation found evidence that a senior planning officer accepted "substantial hospitality" from the applicant, including first class rail travel, hotel accommodation and a meal in a London restaurant owned by a Michelin-starred chef.
The report said the level of hospitality was "excessive" and that the planning officer had not declared it, contrary to council procedures.
"There is consequently doubt on the behaviour and impartiality of this very senior planning officer, who was in a significant position of authority and control, regarding the planning application in question," the report said.
In addition, the report said that the investigation found evidence of discussions between previous senior management at the council and the developer, including discussions held through a chief officer’s personal email account.
"It is now clear that senior officers within the planning department were similarly using personal email accounts to transact county council business in respect of this same planning application," the report said.
A senior planning officer instructed staff to carry out correspondence relating to the application via personal accounts, "in order that the correspondence would be hidden and not be able to be subjected to potential scrutiny through the expected routes such as audit or Freedom of Information processes", the report said.
In addition, the correspondence "demonstrates a colloquial and inappropriate familiarity between senior planning officers and the planning applicant in question", including gossip relating to another planning application, the report found.
The investigation also found evidence that the applicant and/or their advisers "were invited/allowed by a very senior officer in the planning department to write and alter parts of the planning officers’ report to the strategic planning committee".
The applicant was also allowed to view confidential drafts of the report, Lally’s report said.
"There is therefore serious concern of undue influence/conflict of interest on the part of the planning applicant," the report added.
In addition, the report said that evidence was unearthed that county council officers sought to obtain legal advice to support the planning applicant’s stance, ignore objections and advice by other officers and to overturn decisions made within the wider planning team "without any fair or reasonable rationale".
A spokesperson for Northumbria Police told Planning: "Northumbria County Council wrote to us in March last year raising a number of concerns.
"In June, we confirmed in writing that, having considered this information, we could not find anything which would warrant a criminal investigation."
A statement issued by the council last week said that the "employees referred to in this report are no longer employed by the council".