IOWA CITY, Iowa — A trial will determine whether U.S. District Judge Stephanie Rose and an aide discriminated and retaliated against a subordinate attorney when Rose was the top federal prosecutor based in Cedar Rapids, a judge has ruled. U.S. District Judge Richard Kopf rejected the Department of Justice’s motion to dismiss the civil lawsuit brought by former Assistant U.S. Attorney Martha Fagg, a civil lawyer based in Sioux City who had expertise in agricultural fraud cases. The ruling late last week is …