Moreover, reforms are hard to implement, because many countries designed their constitutions to shield police from politicians' meddling.

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Mr Baker said people who had tried to shield Abdalla Yones from police could now be investigated on suspicion of perverting the course of justice.

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They could also handily shield ministers themselves from blame if the police end up doing less for less.

ECONOMIST: Police reform

At the weekend, footage released by Camp for Climate Action protesters showed a police officer striking a man, identified as IT worker Alex Cinnane, with a riot shield.

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