UK law doesn’t prevent photography in public places, assuming that you’re not committing any other offences. However you must respect individuals and their rights and you must not on any account harass people to get the shot you want. However, this changes when you are in a private place, for example a shopping centre or private shop. The key here is to gain approval before you shoot, for example you wish to shoot in the Trafford Centre Manchester, then contact the centre before hand. I have been questioned by Security centre staff whilst taking innocent street photography in the Arndale Centre Manchester.
Quite honestly, these people are only doing their job protecting people and they don’t understand your’e motifs, particularly in the current climate. Be aware also as a street photographer, if you’re photographing something that could be deemed sensitive to national security, then the recent prevention of terrorism legislation could give the police cause to stop you. Having said this, you are perfectly within your rights to photograph people on the UK streets without question and people don’t realise this as you go about your craft. It’s also worth checking the local laws when you travel abroad. More on this later….