The four guests were in a pub in Stockholm in September when they were refused non-alcoholic drinks by waiters and the head bartender.
The guests claimed they were stone-cold sober, and police called to the scene confirmed that none of them was drunk, reported the Dagens Nyheter newspaper (DN). Other guests at the bar attested to this, but the bartender and staff disagreed.
In fact, one waiter told police during questioning that the group of men was acting so pleasantly that the four men must have been on drugs.
"One of the men began waving with his arms," the waiter told the police, adding that the man was acting as if he knew the staff members. "[He] said 'Hello my friend, is all well with you?'"
The four guests claim, however, that their drinks request was refused on the grounds of racial discrimination as they all had black skin.
The head bartender disagreed, stating the men were "unusually pleasant" and that this was a ruse to conceal the fact that they were on drugs or drunk.
Restaurant staff denied any crime. A police investigation has been launched.