Former Bridgeport, Conn., police chief Armando “A.J.” Perez and David Dunn, the city’s acting personnel director, are facing federal charges of wire fraud, conspiracy to commit wire fraud, and making false statements to investigators. Prosecutors say the two men rigged the police chief’s exam two years ago to make sure Perez got the post. They say Dunn gave Perez exam materials, including the oral examination questions. They also say Perez had two other police officers take the written exam for him. Dunn also rigged the grading criteria to favor Perez. Perez resigned hours after his arrest.