DETROIT - Detroit Mayor Kwame Kilpatrick and his former top aide have pleaded not guilty to charges they lied under oath about having an affair.

The mayor and former Chief of Staff Christine Beatty were arraigned Tuesday. Not guilty pleas were entered for them on charges of perjury, conspiracy, obstruction of justice and misconduct in office.

Both are accused of lying under oath about an affair and their roles in the firing of a top police official. Steamy text messages first reported by the Detroit Free Press revealed a flirty, sometimes explicit, dialogue between the two.

Attorneys for both say their clients will be exonerated.