The current issue of 'Private Eye' carries a letter from a member of the British Nazis, which includes the following -

"In 2005 the BNP were asked to send two members to the recording of Question Time to be part of the audience with the implication that they would be heard and allowed to ask questions."

The two members who attended were called on to contribute, and did so, identifying their affiliation. The correspondent continues -

"Certainly not the same as being on the panel, but the 'No Platform for the BNP' policy has been a dead-duck for many years now."

One is led to wonder if the policy ever existed at the BBC.