IOWA CITY — The Johnson County Board of Supervisors is exploring the possibility of bypassing state and federal rates to create a countywide ordinance raising the minimum wage.However, the legality behind such a move — basically whether the county may legally pass such a local measure — remains undetermined, according to the county attorney.Supervisors Mike Carberry, Janelle Rettig and Rod Sullivan requested the topic be discussed at a board work session, which will take place at 10 a.m.