The Criminal Justice Act 2003 allows a policeman to set bail conditions on a person who they have arrested, without even taking them to a police station.
Clearly it is outrageous that a policeman can arrest someone (at a protest for example) and then make up whatever bail conditions they like (leave the area, don't go to Manchester, don't speak to those 4 people) before releasing the person in the street.
Going further back, it was the Criminal Justice and Public Order Act 1994 which allowed the police to set bail conditions at a police station when releasing someone they had arrested.
I think it's wrong that the police can restrict a person's freedom in this way. It should be for a court to set bail conditions, where the suspect's lawyer can argue on their client's behalf that the conditions are too stringent and unnecessary , and the conditions should be no more than are necessary to prevent the investigation and subsequent proceedings being interfered with (IE to stop people intimidating witnesses or repeating the alleged criminal behaviour whilst waiting to be prosecuted).
Why does this idea matter?
Because allowing the police to decide what restrictions they want to put on a person's liberty is wrong and open to abuse, and only a court should have the power to do this, after hearing representations from both parties.