Lieutenant Michael Lohman of the New Orleans Police Department pleaded guilty to obstruction of justice Wednesday—bad news for the other cops involved in shootings on Danziger Bridge that killed two and injured four in the days after Hurricane Katrina. Lohman has admitted to planting a gun at the crime scene and helping to rewrite police reports and witness statements. Prosecutors have sent target letters to at least two other officers, Sgt. Robert Gisevius, who fired his weapon on Danziger Bridge, and Sgt. Arthur Kaufman, who led the internal investigation of the shootings.