Sch 7 para 4
A joint commission inquiring into a referred matter shall— (a) identify and investigate the considerations relevant to, or the technical or scientific aspects of, that matter which in their opinion are relevant to the question whether the proposed development should be permitted to be carried out, (b) assess the importance to be attached to those considerations or aspects, (c) give to persons an opportunity of appearing before, and being heard by, one or more members of the commission in accordance with paragraph 5, and (d) report to the responsible Ministers on the matter.