The death of Ian Tomlinson during the G20 protests in April 2009 and the images of police batons raining down on protestors have put the spotlight on the tactics police deploy during public demonstrations.
Dispatches has been given exclusive access to the Metropolitan Police to find out what training officers are given.
The programme looks at how the police are taught to judge the level of force required to suppress disorder, and examines controversial crowd control tactics like 'containment', which brings protestors face-to-face with heavily-protected and armed police officers.
Dispatches asks why, if the vast majority of protests pass off peacefully, police training still focuses on the worst-case scenario of riots and petrol bombs, and hears from critics of the current training who argue it is out of step with 21st century protest.
The programme examines the evolution of this training and asks whether the requirements of health and safety legislation have had an adverse effect on policing public order: whether the rules designed to protect the police from harm actually put them at greater risk.
And when Climate Camp returned to the capital in summer 2009, Dispatches was there to find out if lessons had been learnt from the events of G20.
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