Coming off a road loss to the Steelers, the Saints went home for an interconference fight with the Cincinnati Bengals.  In the first quarter, Cincinnati struck first with quarterback Carson Palmer completing a 41-yard touchdown pass to WR Chad Johnson.  Afterwards, New Orleans responded with quarterback Drew Brees completing a 72-yard touchdown pass to WR Joe Horn.  In the second quarter, the Bengals took the lead with kicker Shayne Graham getting a 21-yard field goal for the only score of the period.  After a scoreless third quarter, kicker John Carney began the fourth quarter with 24-yard field goal.  However, things went downhill with Cincinnati's most dominant part of the game.  Palmer would complete a 60-yard touchdown pass and a 4-yard touchdown pass to Chad, while rookie DB Ethan Kilmer returned an interception 52 yards for a touchdown.  Afterwards, New Orleans could only muster a 27-yard touchdown pass from Brees to WR Terrance Copper.  With the loss, the Saints fell to 6-4.
Question: Who scored the only defensive touchdown of the game?
Answer: Ethan Kilmer