do a Bertie

Definition

Slang

  • verb to turn Queen’s Evidence, to inform on one’s accomplices. A fairly rare piece of criminal jargon of uncertain origin. It is possibly from the Edwardian era, when turning King’s Evidence would have been joining ‘Bertie’s’ side, and seems to have existed before the days of bertie Smalls, a 1970s criminal supergrass (a high-level informer).
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