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[1920] 122 LT 24 (CA). The claimant was brought to his employer's office to be interviewed in connection with a theft. Although the claimant did not know it, two security guards had been stationed outside and told to prevent him leaving. When the claimant found out, he brought an action for false imprisonment. Lord Atkins said (p. 53):

It appears to me that a person could be imprisoned without his knowing it. I think a person can be imprisoned while he is asleep, while he is in a state of drunkenness, while he is unconscious, and while he is a lunatic...It is quite unnecessary to go on to show that in fact the man knew that he was imprisoned