I guess you're in the UK? The UK has this really weird law where it's legal to listen to anything but you may not repeat what you heard. I don't know of any other country that has that stipulation.
In most of Europe you can listen all you want and talk about it. I think in the US some frequencies were forbidden to listen to and to this day these are blocked on scanners. Not sure why as analog cellphones are long obsolete.
Even listening is in a grey area in the UK; it’s a separate offence to “use wireless telegraphy apparatus with intent to obtain information as to the contents, sender or addressee of any message” where you aren’t an intended recipient. But the intent bit is probably hard to prove in practice.
Of course listening to ham radio bands is allowed since they are meant to be public. But unlike in other countries the UK does mind if you speak about what you heard on the bands. I've heard several people getting berated for this on the bands.
I suppose for stuff that's actually meant to be prive it's even illegal to intercept it, I don't know. Personally I think such laws are just theater. Just like the cell band blocking on scanners in the US. Spend 2 minutes on mods.dk and a soldering iron and problem solved.
In most of Europe you can listen all you want and talk about it. I think in the US some frequencies were forbidden to listen to and to this day these are blocked on scanners. Not sure why as analog cellphones are long obsolete.