State prosecutors are asking a judge to dismiss criminal charges against former state Senator Lowell Barron and former aide Jill Johnson. Prosecutors filed the request late yesterday in DeKalb County. The state cites a series of court rulings against the prosecution in their request to throw out the case. A judge ruled prosecutors could not present evidence about whether Barron and Johnson had a romantic relationship. The judge also said the defense could present evidence about how other candidates used campaign money. Those decisions stood on appeal, killing the state's case. A grand jury indicted Barron and Johnson last year on campaign finance and ethics charges. The two were accused of using campaign money to help Johnson pay off a home loan.