It also called for improved community participation through public funding. It was responding to the government's consultation on the Infrastructure Planning Commission (IPC) examination procedures, which ended this week.
The CPRE said that if the IPC controls the procedure to the full extent of the Planning Act 2008, the process will lack public legitimacy and will be open to judicial review.
The body wants the right to cross-examine cases and for statements to be heard in person. It called for evidence to be tested through hearings, not solely by written representations.
Despite insisting that decisions on nationally significant infrastructure projects are best made by ministers or local authorities, the CPRE concedes that some projects in the scope of the act may be uncontroversial.
It called for an independent regulator with an environmental remit such as the Environment Agency to have an assessor role. This would be beneficial where the IPC is unable to recruit a commissioner with specific expertise, it argued.