Public Order (Preservation) Act 1958 · Updated to 1 Apr 2013 · Part III · Powers for Maintenance of Public Order
6. Barriers
Feedback & supportA police officer may, for the purpose of giving effect to an order or direction made under section 4, or whenever he considers it necessary so to do for the preservation of law and order or for the prevention or detection of crime, erect or place barriers in or across any road, street, path, waterway, or public place in a proclaimed area in such manner as he may think fit.
police officer
"police officer" includes a volunteer reserve police officer and auxiliary police officer appointed in accordance with any written law for the time being in force;
A police officer may take all reasonable steps to prevent any person, whether on foot or in a vehicle or vessel, from passing any such barrier and every person shall comply with any direction or signal of any such officer requiring the person to stop at or before reaching any such barrier.
A police officer may use such force as may be necessary to prevent any person from passing any such barrier, which force may extend to the use of lethal weapons.