There is a law which restricts people from listening to Live ATC from UK airports. Whilst not an issue from most, I think it is a relatively pointless and outdated law which helps no one. It prevent people who enjoy aviation from listening in whilst at home or even plane spotting.

In countries like the USA they are allowed to Listen to Live ATC and I think it is very interesting. People with a passion are unable to learn from some of the best Air Traffic Controllers in the world at the moment.