Can a policeman listen at an open window even though standing in the owner's flower bed?

It has never been thought that the principle of law embodied in the expression "a man's home is his castle" was breached by a policeman listening at an open window even though standing in the owner's flower bed. In Ghani v. Jones (1970) 1 A.B. 693, Lord Denning had this to say about trespass at page 705: "The first thing to notice is that police officers had no search warrant. The reason is simple. No magistrate - no judge even - has any power to issue a search warrant for murder. He can issue a search warrant for stolen goods and for some statutory offences, such as coinage. But not for murder. Not to dig for the body. Nor to look for the axe, the gun or the poison dregs. The police have to get the consent of the householder to enter if they can: or, if not, do it by stealth or force. Somehow they seem to manage. No decent person refuses them permission. If he does, he is probably implicated in some way or other. So the police risk an action for trespass. It is not much risk." I am of the opinion that that principle is not breached by the placing of a transmitter surreptitiously or by a trick within private premises.