R v Collins 1973 QB 100 was a unanimous appeal in the Court of Appeal of England and Wales which examined the meaning of "enters as a trespasser" in the definition of burglary, where the separate legal questions of an invitation based on mistaken identity and extent of entry at the point of that beckoning or invitation to enter were in question.
She was somewhat inebriated when they parted and she went to bed; she slept naked that July night in her room, the location of which the defendant knew having done some work in the house.
At 02:00 the defendant climbed the ladder and, alleging much dutch courage, caught sight of the sleeping woman, stripped to his socks, and rested kneeling on the sill - he "was just pulling [him]self in" to ask for sex when the victim awoke, and immediately believed she was greeting her boyfriend.
The defence barrister submitted during the trial that because she had invited him into her bedroom, even under a mistake of fact, Collins had not "entered as a trespasser".
At least two were not put to the jury:- The point in issue had never been adjudicated one so there was no authority on which the court could rely; instead, three completing analyses of the most distinguished textbooks were weighed up.