Stanhope chairman Sir Stuart Lipton has failed in his attempt to bring a charge of professional misconduct against a local politician who drew attention to alleged conflicts of interest at CABE.

The Royal Town Planning Institute inquiry was established after Lipton’s solicitor, Linklaters, sent it a dossier accusing Adrian Dennis, a member of the institute and the cabinet member for regeneration at Croydon council, of professional misconduct.

The complaint centred on evidence submitted by Dennis to the House of Commons housing and planning select committee’s inquiry into CABE in which he accused Lipton of “engaging in activities for personal gain which have brought the planning system into disrepute”.

But the institute has dropped its investigation after it was advised that it was in danger of breaching parliamentary privilege if it disciplined a member for comments made to the House of Commons.

The select committee is also preparing a report on what steps it could take against Linklaters.