Last summer, as the Austin fire union was preparing to represent one of its members at a disciplinary hearing, department officials permitted union president Bob Nicks to review confidential documents in the case under a provision of the city’s labor contract with firefighters. With a couple of clicks, Nicks secretly downloaded the information onto his personal laptop — but says he disclosed what he’d done a few days later to top department officials. But his actions led to an unusual punishment from Fire Chief Rhoda Mae Kerr: She banned him from representing any other firefighter at a disciplinary hearing for more than a year — a punishment that strikes at the core of one of his primary duties as union president. The issue highlights a dispute that has escalated between Kerr and Nicks over the past several years.