As part of reforms to police recruitment rules being unveiled today, the Home Secretary is expected to announce that candidates from the US, Canada, Australia and New Zealand, among others, will be able to front up forces in England and Wales.
Current legislation prevented US "supercop" Bill Bratton, former head of the New York police, applying to take charge of the Metropolitan Police in 2011.
Mr Bratton gained a reputation for introducing bold measures to reduce crime, heading police departments in New York, Boston and Los Angeles.
In his first two years at the helm of New York Police Department, reports of serious crime dropped 27%.
But Mrs May dashed any chances of him becoming Britain's top police officer when she underlined the importance of the Scotland Yard commissioner being a British citizen for national security reasons.
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