Some 76 venues across the capital have been voluntarily trialling the breathalysers and reported a drop in violence since their introduction earlier this year.
The Metropolitan Police has confirmed plans to extend the initiative into next year as a result of promising feedback.
The breathalysers have been introduced in Westminster, Kingston, Wandsworth, Lambeth, Croydon, Havering, Enfield, Islington, Kensington & Chelsea, Hackney, Newham and Harrow.
Their use at pubs has been met with opposition from industry leaders, but sergeant Ian Martin, a licensing officer at the Met, told the Publican’s Morning Advertiser (PMA) that with violent crime rates on the rise, pubs and late-night venues need to work with police to make customers’ nights out safer.
Last month, the PMA revealed that violent crime at London pubs had jumped by 24% in 2014.
In an exclusive interview with the PMA, Martin said: “Much of the time, violence is driven by alcohol. We’re living in an age of diminishing resources and budget cuts. We need to find new ways to help premises.”
He assured pubs there were no plans to insist on breathalysers as a condition on licences. But he urged a “co-ordinated effort from the high street” on the scheme.
The device was offered to all operators in the boroughs where they were trialled, but some pubcos refused, including Stonegate and Wetherspoon. Both pubcos said they didn’t feel it was “appropriate” to breathalyse customers and were confident in their staff keeping pubs safe and legal.
Trade leaders have expressed caution about the unintended consequences of their use. British Beer & Pub Association chief Brigid Simmonds previously warned their use risked “turning pubs into fortresses” and would encourage customers to drink at home.
Tom Watson, an ex-Met Police sergeant and London representative for PubWatch, labelled the devices as “pointless”.
But Ian Graham, chief licensing officer at the Met, insisted that breathalysers remained an on-the-door “tool”, and were not being used inside to police venues.
“Door staff already know if they’re going to let someone in or not, and you can’t have an argument with a machine,” he said.
Councils across the country have been trialling their use, including Norwich, Newquay, Nottinghamshire and Leicestershire.