The photographs and ensuing video footage immediately raised questions about policing of the protest.

The subsequent death of Tomlinson turned the spotlight on the tactics police deploy during public demonstrations. At the time of the protest, much was made of Tomlinson’s death with friends and relatives firmly pointing the finger of blame in the direction of the police.

In another ground-breaking documentary, Dispatches has been granted exclusive access to the Metropolitan Police to discover what training officers are given to prepare them to deal with mass protests.

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 protesters face-to-face with heavily protected and armed police officers.

The show raises interesting questions, such as: if the overwhelming majority of protests pass off peacefully, why is the police training so focused on the worst-case scenario of riots and petrol bombs?

Perhaps unsurprisingly, there are plenty of critics all too keen to voice their opposition to this type of training, claiming it has no place

in 21st-century Britain. Most modern protests, they argue, rarely turn violent and it’s the actions of the police which often inflames an otherwise peaceful protest.

Dispatches returned to London this summer for the Climate Camp protest to witness first-hand if the police had learned any lessons from the G20 march.

DISPATCHES: READY FOR A RIOT, Channel 4, 8pm