Mr Justice Toulson has agreed to view the hour-long X-rated video to decide whether it sheds any light on the damages case brought against the hypnotist.

Mr McKenna is being sued for �200,000 by Christopher Gates, a participant in one of his UK stage shows. Mr Gates says that he developed schizophrenia after being hypnotised. Mr McKenna denies negligence.

Just for laughs

Gates: Suing for �200,000 damages

The tape of the Howard Stern Show features a woman having an orgasm under hypnosis and a man who has been persuaded by Mr McKenna to believe he has lost his penis.

Mr Gates's QC, Anthony Scrivener, said it was necessary for the judge to see the tape because he was trying to establish that Mr McKenna "used inappropriate acts which put people under considerable distress".

'I did not deceive them'

Mr Scrivener suggested to Mr McKenna that he had deceived the woman into having an orgasm on the American programme.

Mr McKenna responded: " I explained to the ladies who were participating what was going to take place and, under hypnosis, I offered that suggestion, but I did not deceive them."

Mr McKenna agreed that he was under a duty to maintain proper ethical standards and that the welfare of the subject should be at the forefront of his mind.

Any time a volunteer on stage showed signs of distress during a show they were taken aside and helped.

'No signs of distress'

Mr McKenna also said he could not recall anyone being distressed by his "lost penis" routine. He said he had performed it many times and it had never seemed inappropriate.

Christopher Gates, 30, says he has suffered psychiatric injury through being hypnotised at the Swan Theatre in High Wycombe in March 1994.

Nine days after the show, Mr Gates was admitted to hospital suffering from schizophrenia. His mental problems have continued. He says he still hears voices in his head and he is now unemployed.