Following this week's revelations about lobbying, the Independent reports today that "the trade body which represents the UK's public relations and lobbying industry is to investigate Bell Pottinger over claims made by executives during a business pitch to undercover reporters".

A rival lobbyist, Mark 'stand up for lobbying' Adams, has made the complaint to the Public Relations Consultants Association (PRCA), one of three trade bodies running the lobbying industry's system of self-regulation. 

Adams states: "I am a strong proponent of self-regulation for the lobbying industry...Ideally Bell Pottinger will clear their name and demonstrate they have done nothing wrong. But if they have behaved in an unethical manner, then the appropriate sanctions should be taken against them."

The toughest sanction available to the PRCA is that they terminate Bell Pottinger's membership. That's it. And you thought the Press Complaints Commission lacked teeth. 

So the worst that can happen is that Bell Pottinger gets chucked out of the club. The result would be that they would no longer be required (under the PRCA rules) to declare their lobbyists and clients on a voluntarily register. They would join the scores of other agencies who choose to stand outside the system and remain in the shadows. 

This would probably suit Bell Pottinger down to the ground. Only three years ago Bell Pottinger Public Affairs' chairman, Peter Bingle, openly told a committee of MPs that he was opposed to transparency. Committee member Paul Flynn MP addressed Bingle: "You've worked for mass murders, racists, people who've oppressed their own people...Doesn't the public have a right to know who your clients are?" No, Bingle replied, "the public has no right to know."

This is a test of the system of self-regulation. If the PRCA refuse to act, and Bell Pottinger is let off the hook (it does appear to be in clear breach of the PRCA's code), self-regulation will be seen for what it is: 'little better than the emperor's new clothes' is how the Committee of MPs described it. The system was designed by lobbyists as a way to head off statutory regulation.

But if the PRCA comes down hard on Bell Pottinger, the firm will be free to operate outside of the system, without any public scrutiny at all.

If anything underlines the need for a statutory register of lobbyists, which would compel lobbyists to operate in the open, it's this.