The Chatham House Rule
"Under the Chatham House rule, anyone who comes to a meeting is free to use information from the discussion, but is not allowed to reveal who made any particular comment.
It is designed to increase openness of discussion.
The rule is a system for holding debates and discussion panels on controversial topics, named after the London headquarters of the Royal Institute of International Affairs, where the rule originated in June 1927."
The rule is designed to promote openness of discussion of public policy and current affairs, as it allows people to express and discuss controversial opinions and arguments without suffering the risk of stalling their career or even dismissal from their job, and with a clear separation from the opinion and the view of their employer.
The rule allows people to speak as individuals and to express views that may not be those of their organisations, and therefore encourages free discussion. Speakers are free to voice their own opinions, and to contest the opinions of other participants, without concern for their personal reputation or their official duties and affiliations. The Chatham House Rule resolves a boundary problem faced by many communities of practice, in that it permits acknowledgement of the community or conversation, while protecting the freedom of interaction that is necessary for the community to carry out its conversations. It is designed to reduce the risk of what has come to be described as groupthink, where unpopular views are excluded from discussion, reducing the range of opinions an organisation can discuss.