The Government should make it a requirement for an officer in uniform to be present in order for an individual to be arrested or detained. Police officers should be visible for the safety of the general public.
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Currently police officers can arrest a civilian while otherwise off duty, and out of uniform, and only have to show their warrant card.
The Met has advised people to ask "searching questions" which puts the responsibility onto civilians and not the officer. Just showing a police warrant card not only makes it easy for someone to impersonate an officer, but also for a legitimate officer to abuse their powers. Public safety is at risk.