Some form of "tribunal" to consider grievances and possibly compensate bank customers is under discussion, at least on the back benches of Australia's governing Liberal and National parties.Senator John Williams and MP Warren Entsch, both from the National Party, are two originators of the tribunal model, a concept that may be intended to fashion an alternative measure to a Royal Commission as championed by the Labor Party and the Greens.The tribunal concept has drawn support from at least one Liberal MP and polite interest from members of the coalition's cabinet.Labor seems certain to make a Royal Commission on banking and finance a feature of the resumption of parliament from the end of the month, with the Opposition in a position to engineer some form of fresh banking inquiry through the Senate.