Three Honolulu police officers caught up in the ongoing corruption scandal involving former Police Chief Louis Kealoha and his prosecutor wife, Katherine, pleaded not guilty Wednesday to criminal charges stemming from allegations they framed someone to help out their boss.

Derek Hahn, Gordon Shiraishi and Minh-Hung “Bobby” Nguyen are three of the six co-defendants named in an Oct. 20 indictment from a federal grand jury that alleged they took part in a mass conspiracy that included bank fraud and forgery.

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The three men were part of a covert unit within the Honolulu Police Department — known as the Criminal Intelligence Unit — when they allegedly took part in the framing of Gerard Puana, Katherine Kealoha’s uncle, for the theft of her mailbox.

Hahn, Shiraishi and Nguyen, each of whom faces separate charges, are also accused of lying to investigators and the federal grand jury in their attempt to cover their tracks.

Hahn has been described by federal authorities as the ringleader of the alleged conspiracy to set up Puana. He also once owned a business with Katherine Kealoha.

Cory Lum/Civil Beat

Hahn has been charged with five felonies related to the allegations that he and others within the Honolulu Police Department manipulated evidence and lied to federal investigators in an attempt to lock up Puana for the theft of the mailbox and cover their tracks.

Nguyen, who was once married to Katherine Kealoha’s niece, faces similar charges for his part in the mailbox case. He has been charged with five felony counts, including conspiracy, making false statements and obstruction.

Shiraishi faces one count of obstruction of an official government proceeding, a felony. He’s accused of lying to the federal grand jury that was investigating the Kealohas.

Shiraishi retired from the HPD in April as a major. At the time of the alleged mailbox theft he was a captain in the CIU. Shiraishi was in the same recruit class as Louis Kealoha in 1983.

The attorneys for Hahn, Shiraishi and Nguyen declined to comment on Wednesday’s arraignment and plea.

Magistrate Judge Richard Puglisi held a closed-door hearing with Nguyen and his attorney, Randall Hironaka, over what was described in court as a confidential personal matter.

Puglisi did not give any explanation as to why he was closing the proceeding to the public.