A Thomas Shaw Thompson wrote to Partridge asking him to send him an ABCR ("aviary bred, close ringed") bramblefinch hen and enclosed a cheque for 30s.

Partridge was charged by Anthony Ian Crittenden, on behalf of the RSPCA, with illegally offering for sale a live wild bird which was not a close-ringed specimen, bred in captivity, contrary to s. 6(1) and Sch.

The magistrates decided that the advertisement was an offer for sale and that the bramblefinch hen was not a close-ringed specimen bred in captivity, because it was possible to remove the ring from the bird's leg.

It was held that the advertisement in question constituted in law an invitation to treat and not an offer to sell; therefore the offence with which the appellant was charged was not established.

The case arose because in a periodical known as "Cage and Aviary Birds", the issue for April 13, 1967, there appeared an advertisement inserted by the appellant containing, inter alia, the words "Quality British A.B.C.R.

"Having been referred to the decision of this court in Fisher v. Bell the justices nonetheless took the view that the advertisement did constitute an offer for sale; they went on further to find that the bird was not a close-ringed specimen bred in captivity, because it was possible to remove the ring.

For my part I confess I was in ignorance, and in some state of confusion, as to the real meaning and effect of this particular phrase in the section, and I express my indebtedness to Mr. Havers, for the prosecutor, for having made the matter, as far as I am concerned, perfectly clear.

In this case what is contemplated, according to Mr. Havers, and I accept it, is that with a young bird of this sort between three and ten days after hatching a closed-ring of the type described is forced over its claws, which are obviously brought together so as to admit the passage of the ring, and it is then permanently on or around the bird's leg, and as it grows, it would be impossible to take that ring off because the claws and the like would have rendered a repetition of the earlier manoeuvre impossible.

..." Lord Parker CJ, in giving judgment said: "The sole question is whether the exhibition of that knife in the window with the ticket constituted an offer for sale within the statute.

I confess that I think that most lay people and, indeed, I myself when I first read the papers, would be inclined to the view that to say that if a knife was displayed in a window like that with a price attached to it was not offering it for sale was just nonsense.

In ordinary language it is there inviting people to buy it, and it is for sale; but any statute must of course be looked at in the light of the general law of the country.

I should perhaps in passing observe that the editors of the publication Criminal Law Review had an article dealing with Fisher v. Bell in which a way round that decision was at least contemplated, suggesting that while there might be one meaning of the phrase "offer for sale" in the law of contract, a criminal court might take a stricter view, particularly having in mind the purpose of the Act, in Fisher v. Bell the stocking of flick knives, and in this case the selling of wild birds.