'Cocaine torch' fails drug detection test

Ultra-violet torches bought by police to check for cocaine use do not always work, a test carried out for Newsbeat suggests.

Merseyside Police are encouraging door staff at bars and clubs in Liverpool to shine the lights on customers' faces.

The force says the torches are just one tactic being used to address drug-related violence, and that anything which discourages illegal drug use is a benefit.

One UK distributor says the torches have several functions including identifying Smartwater, counterfeit currency and security features on credit cards.

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