Trade leaders have condemned a controversial drugs-swabbing scheme carried out by police as a condition of entry to pubs in towns across Sussex.
Drinkers are required to queue for admission to licensed premises and agree to swab samples - which will be checked by officers for traces of illegal substances.
Plain-clothes officers will be present to detain any person who refuses the test and decides to leave the queue.
Trade groups say the scheme opens up worrying civil liberty issues and could affect trade at scores of pubs and clubs.
Swab tests will be conducted at random in selected licensed premises, according to police.
Morning Advertiser legal expert Peter Coulson said: "These plans are out of all proportion and to involve the trade in such an initiative without some form of national policy or legislation is a step too far.
"It places licensees between a rock and a hard place in terms of customers and the police but I am particularly concerned about the queue drop-out scenario.
"People may wish to drop out of a queue on principle, but that shouldn't raise suspicion of drug carrying and it smacks of guilty until proved innocent," he said.
Licensees in the East Sussex town of Lewes were given details of the scheme by police at a pubwatch meeting.
One town-centre host said: "I can see this being exceedingly unpopular with any law-abiding citizen.
"Customers will simply not turn up at a pub if they suspect they are going to have to go through this sort of testing.
"We want to work with the police in the fight against drugs but we have to balance this with the effect that swab testing might have on business.
"I have grave concerns about the implications for my licence and livelihood."