Two concertgoers detained by police before a Bruce Springsteen show this summer have sued the Foxborough police chief, claiming they were illegally held under a policy in which police round up people they think are drunk. The suit by Paul Weldner and Dr. Timothy Dutton, both of the Portland, Maine area, was filed Monday against Chief Edward O’Leary in federal court. Weldner said officers detained him for hours, claiming he was drunk, after he stumbled briefly while walking to the August show at Gillette Stadium. Dutton said he was detained after he objected when police took his girlfriend into custody. The complaint says both men were drinking, but neither was “incapacitated” – the state’s legal standard for putting people into protective custody. They’re suing for unspecified damages. O’Leary said he hadn’t seen the brief Monday and couldn’t comment.