From Liberty
http://www.liberty-human-rights.org.uk/issues/6-free-speech/s44-terrorism-act/index.shtml
YOUR RIGHTS UNDER SECTION 44:
The police can only give you a pat down, remove outer clothes (eg jacket, hat), search your bags and have you empty your pockets
You do not have to give your name and address
You do not have to explain why you are there
You are not allowed to flee the search, but you are not required to be actively compliant. You are allowed to 'go limp' as passive resistance during the search if you wish not to comply
There is no permission to collect DNA data during the search
You do not have to comply with any attempt to photograph or record you
Women cannot be touched by male police during these searches
Make notes about the officers searching you - name, number and police force
Note the time and the events preceding the search
Note the specific wording used by the police to explain their authority to search you
Ask the police for the reason that they are searching you. Specifically, are they searching for terrorists or are they simply trying to deter, delay or inconvenience you?