Dennis Mitsunaga is going on the offensive. 

The CEO of a Honolulu engineering firm, Mitsunaga is facing charges of trying to buy the prosecution of a former employee. If convicted of bribing former prosecutor Keith Kaneshiro, the 79-year-old could go to prison for the rest of his life. 

But in new court filings, Mitsunaga’s legal team said the investigation and grand jury process led by San Diego-based Assistant U.S. Attorney Michael Wheat was so crooked that the whole case must be thrown out. 

Nina Marino, Mitsunaga’s Los Angeles-based attorney, is accusing prosecutors of “intruding” into the attorney-client relationship Mitsunaga and his employees had with the firm’s lawyer, Sheri Tanaka, who is charged in the case. 

Marino says prosecutors also accepted false testimony before the grand jury and misled witnesses into thinking they were not targets of the investigation in order to secure their testimony. They were later charged.

It all amounts to “outrageous prosecutorial misconduct,” Marino wrote. 

Federal court in Hawaii “cannot and should not be relegated to housing a graveyard of due process rights trampled and discarded under the false banner of the pursuit of justice,” she said. 

“Because these acts of prosecutorial misconduct collectively shock the conscience, the very essence of justice demands that this case be dismissed.”

Kelly Thornton, a spokeswoman for the Department of Justice, declined to comment. Prior attempts to get the case dismissed on other grounds were unsuccessful.

Wheat has been investigating and prosecuting public corruption cases in Hawaii for the better part of a decade. In 2015, he was brought in as a special prosecutor to tackle the scandal that put former deputy city prosecutor Katherine Kealoha and her husband, ex-police chief Louis Kealoha, in federal prison. 

He has since secured indictments against three other former city officials who arranged Kealoha’s $250,000 severance agreement. In that case, too, defense attorneys accused Wheat of prosecutorial misconduct. The judge in that case, Leslie Kobayashi, has expressed skepticism about those claims and other efforts to dismiss the case, but she has yet to rule. 

Marino pointed to those accusations in her filing, suggesting the prosecution team has a history of misconduct. 

Ali Silvert, a former federal public defender, said it appears Mitsunaga’s team is trying to take Wheat down a notch in the eyes of the public and the judge.

“There seems to be a concerted effort to demystify, desanctify Wheat in the motions that were filed in the Leong case and in this one,” he said. “They’re trying to put it out there that Wheat is not a savior coming to save Hawaii but is really a crooked prosecutor who will do anything to get a conviction.”

Silvert said the defense’s legal arguments have enough merit to be heard by a judge.

“I do think it’s a valid challenge that needs to be aired in front of a court,” he said. “If the prosecutors overstepped their bounds, the court should take action. If they didn’t, the court should educate us and rule so we the public can understand: What can a prosecutor do, and what can’t they do?”

In Mitsunaga’s case, Marino says the feds secretly targeted Tanaka for more than a year, even as they knew she was representing Mitsunaga in the same grand jury investigation. This became a problem, according to Marino, who cited a 2021 meeting between Tanaka and Wheat. 

“During that meeting, because Tanaka was a target of the same investigation, the prosecution did not provide meaningful or substantive information regarding the allegations against Mr. Mitsunaga,” Marino said. 

“Attorney Tanaka was therefore rendered ineffective, and Mr. Mitsunaga was actually and substantially prejudiced as a result.” 

During the grand jury proceedings, Tanaka represented at least 22 witnesses in addition to Mitsunaga. Marino argues the feds used Tanaka’s attorney-client relationship with those people to “create suspicion in the minds of the grand jurors.”

“Collectively, the prosecution’s lines of questioning strongly implied that Ms. Tanaka was untrustworthy” and that, by extension, all Mitsunaga employees were “not credible, and their testimony suspicious,” according to Marino.

Marino also takes issue with the grand jury testimony of HPD Det. Phillip Snoops. The detective told grand jurors that he only spoke to Mitsunaga’s team once about an alleged theft by a former employee, Laurel Mau, and that he “never got any piece of evidence from them at all,” according to Marino’s filing. 

That wasn’t true, Marino says. But it was useful for the prosecution to imply that Mitsunaga & Associates had “abandoned the ‘conventional’ route” of going through the police and had instead established a direct line of communication with Kaneshiro, she said.

Grand jurors were also given the false impression that Mitsunaga and his colleagues all donated to Kaneshiro’s reelection campaign on the same days, according to Marino. In fact, the dates indicated on campaign finance reports reflect the day on which they were deposited, she said, not when the checks were written.  

Nevertheless, the prosecution repeatedly asked witnesses why they made political contributions on the “same day” as their colleagues.

“The prosecution’s narrative that the campaign contributions were made on the same day is central to the conspiracy theory,” Marino says, adding that the “misrepresentation” could have made the difference between securing an indictment or not. 

Marino also objects to prosecutors calling people to testify before the grand jury as witnesses when, in her view, they should’ve been informed that they were “targets.” 

Another witness who was ultimately charged, Terri Ann Otani, said prosecutors “tricked” her into sharing notes with the grand jury even though they should’ve been protected by her constitutional right against self-incrimination. 

U.S. District Court Judge J. Michael Seabright will consider Marino’s motion to dismiss. Currently, a trial is scheduled for Feb. 27.