HONOLULU — A retired U.S. Navy commander in Hawaii must spend 18 months in federal prison for lying about his relationship with a Malaysian defense contractor nicknamed “Fat Leonard.”

A federal judge in Honolulu sentenced David Kapaun on Monday, saying he abused his position in the Navy to help give a contractor an unfair advantage.

Leonard Francis has admitted bribing Navy officials with cash, prostitutes and other gifts in exchange for information to help his company. He’s awaiting sentencing.

Prosecutors say Kapaun was one of the officials Francis plied with those gifts. Kapaun must pay $50,000 in restitution and a $25,000 fine. He must also serve 200 hours of community service.

Kapaun pleaded in guilty in June, saying he lied when didn’t disclose on a security clearance form his connection to Francis.