HONOLULU (HawaiiNewsNow) - The key witness in the federal probe into the police chief and his wife, a deputy city prosecutor, is a police officer who was related by marriage to the power couple.
Officer Bobby Nguyen has testified before a federal grand jury involved in the case multiple times, Hawaii News Now has learned.
He's the man in the middle of a tangled web involving police Chief Louis Kealoha and his wife, Katherine, a high-ranking deputy city prosecutor.
Nguyen was married to Katherine's niece, Maile Nguyen, also a police officer. And that marriage thrust him into the center of a bitter, financial fight between the Kealohas and other relatives, the Puanas.
Nguyen appears to be involved in key moments of that dispute, sources say.
On June 27, 2011, Nguyen was at the Puanas' Wilhelmina Rise home when Katherine Kealoha allegedly went inside and took items, including cash, sources say. The federal grand jury will decide if these actions could constitute an illegal search and seizure.
Two years later, on June 21, 2013, the Kealohas reported that their mailbox was stolen.
The Nguyens were living on the Kealoha's Kahala property at the time, and Bobby Nguyen was the first to tell investigators that the man in the grainy surveillance video was Katherine Kealoha's uncle, Gerard Puana.
Puana, was charged, but those charges were dropped.
And the case triggered the FBI's investigation into whether the mailbox theft was staged to discredit the Puanas in a civil trial at the center of the financial fight.
As both the mailbox case and the financial dispute headed into court so did the Nguyens' marriage. During a bitter divorce battle, Maile Nguyen filed temporary restraining orders.
In one TRO request, she claims, her husband "has been uncooperative regarding my family's lawsuit."
She writes, "I was afraid to speak up because he wouldn't show up" for court proceedings. She also says that he was "the only witness to positively" identify Puana as the mailbox thief.
Nguyen has been called to testify before the grand jury several times, and it's clear his proximity to many of the key events surrounding the case makes him a very important witness.
"If he's gone before the grand jury on numerous occasions, clearly, they need him and they want information and obviously he has it or they wouldn't have called him that many times," defense attorney William Harrison said.
There's yet another connection: One of Bobby Nguyen's lawyers was Jake Delaplane, who was part of the Honolulu prosecuting attorney's team on the controversial, failed crackdown on gaming machines. Delaplane's partner on that case: Katherine Kealoha, who is head of the career criminal unit.
Delaplane would not comment on his appearance at federal court. But sources say he is representing other grand jury witnesses, too.
Hawaii News Now did reach out to Bobby Nguyen for comment. He declined to speak.
HNN also reached out numerous times to the Kealohas for comment on the federal investigation. They have also declined to comment.
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