A landmark judicial review of police practices at last year's Royal Wedding will begin later.
Measures examined will include the use of 'pre-crime' arrests - which were employed before the wedding.
The findings will likely impact future policing at upcoming events such as the Jubilee and Olympics.
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A 24-year-old man has been arrested on suspicion of murder after the body washed up on the Thames shoreline.
Seven people have now been arrested after a man died from serious head injuries
The 38-year-old officer was on his way home from a night shift when he collapsed. His death is not being treated as suspicious.