The inquiry to decide whether the controversial £148.5m Norwich Northern Distributor Road should go ahead is to be overseen by a panel of inspectors rather than just one.

The panel has been appointed after communities secretary Eric Pickles decided the case was so complex and had such a high level of public interest in it that it was more appropriate for three inspectors, rather than just one to consider it.

Planning inspector Elizabeth Hill had been due to weigh up the evidence during a number of hearings this summer, before making a recommendation to the secretary of state on whether to grant a development consent order.

But now inspectors Peter Robottom, Austin Smyth and David Richards have been appointed as the examining authority to preside over the hearings into the 19.5km dual carriageway road, which Norfolk County Council wants to build from the A47 at Postwick in the east of the city to the A1067 Fakenham Road to the northwest.

The government has agreed to contribute £86.5m towards the cost and has said the scheme is of 'national significance', which has fast-tracked it through the planning system.

The road has met opposition from Friends of the Earth, the Campaign to Protect Rural England (CPRE), Stop Norfolk Urbanisation (SNUB) and the Green Party, who say it will increase congestion and lead to swathes of the countryside being concreted over.

They, along with the Norfolk and Norwich Transport Action Group and Hockering Parish Council, have jointed forces to produce a dossier which they say shows the flaws in the public consultation.

Among their complaints was that submissions from the Green Party, campaign group Stop Norwich Urbanisation (SNUB) and the Campaign to Protect Rural England, that their submissions over the road were lost.

That sparked an investigation at Norfolk County Council, conducted by Al Collier, head of procurement, which concluded he was 'unable to arrive at a definitive view as to what happened'.

Katy Jones, branch manager of CPRE Norfolk said: 'This is an astonishing catalogue of legal and procedural mistakes, mainly by Norfolk County Council, who are trying to force through the NDR on very spurious grounds.

'They are obliged to consult and then consider the views of the public and affected parties, but they have failed to do this correctly throughout the process.'

They have sent their report to the panel of planning inspectors and urge them to recommend that Mr Pickles should refuse the county council's application.

The first of the open hearings over the road are due to take place in Norwich and Thorpe St Andrew on Tuesday, July 22, with a site visit the next day.

Norfolk County Council says the road will bring a huge economic boost and improvements, such as a rapid bus transit in Norwich.

• What do you think of the NDR? Write, giving full contact details, to Letters Editor, Prospect House, Rouen Road, Norwich NR1 1RE.