A Commons Select Committee inquiring into the Government's HS2 high-speed rail project has commissioned an independent review into the £32 billion scheme rather than just rely on written and verbal evidence, it was announced tonight.
From the independent consultants Oxera, the review is due to be published tomorrow as the House of Commons Transport Committee holds the first of five evidence sessions on HS2.
The review focuses on the business case for HS2 whose first part - from London to Birmingham is due to be completed in 2026.
A second Y-shaped section on to Manchester and Leeds and possibly further north could be finished around 2032/33.
Announcing the Oxera review, the House of Commons Transport Committee chairman Louise Ellman (Lab: Liverpool Riverside) said: "The review is a guide for us. We felt we needed it. This is a project of great importance and also of great controversy."
The coalition Government is anxious to press ahead with HS2 which is the central plank of its whole transport policy.
"We want the review to look at some of the technical assumptions about the Government's case for HS2, Mrs Ellman said.
The inquiry will not look at the precise specification of the HS2 route which passes through beauty spots in traditional Tory heartlands.
The committee will also not look at how the route will affect landowners, businesses and residents.
But it will investigate if the project is justified on cost grounds, whether the passenger numbers add up, whether the project will lead to a modal shift from road to rail and whether other schemes might be more appropriate.
As many as 190 organisations have submitted written evidence to the committee.
Mrs Ellman was asked about a Sunday Times report that the Duke of York had told the Treasury last year that the Queen was concerned that high-speed trains could spook her horses.
Mrs Ellman was asked: "Has the Queen made representation to the committee? Smiling, Mrs Ellman replied; "Not that I have seen up until now."
Among those giving evidence to the committee tomorrow are the Association of Train Operating Companies' chief executive Michael Roberts and Network Rail network planning director Richard Eccles.
Supporters of HS2 will appear before the committee on June 28, while the main opponents of the scheme will give evidence on July 12.
Aviation and environmental groups are due to appear on September 6, with Transport Secretary Philip Hammond giving evidence to the committee on September 13.