Bookie for Shohei Ohtani’s former interpreter will plead guilty to illegal gambling charges

An Orange County bookie whose clients included Ippei Mizuhara, the former interpreter for Dodgers superstar Shohei Ohtani, has agreed to plead guilty to federal charges for running an illegal gambling business.

As part of a plea agreement unsealed Thursday, Mathew Bowyer, 49, was charged in U.S. District Court in Santa Ana with operating an unlawful gambling business, money laundering, and signing a false tax return.

The agreement said Bowyer’s gambling business had “more than 700 bettors at times� and “often had gross revenue of well over $2,000 on a single day.� Customers included a “professional baseball player for a Southern California baseball club� and a “former minor league baseball player.� Neither player was named.

The ex-minor league player’s bets included baseball games in which the “professional baseball player� participated, according to the agreement.

Bowyer is expected to enter his plea on Aug. 9, federal authorities said, and could face up to 10 years in prison on the money laundering count, up to five years for the unlawful gambling business count and up to three years for the false tax return count. He has agreed to “cooperate fully,� authorities said.

Diane Bass, Bowyer’s attorney, said her client “is looking forward to accepting responsibility for his actions.�

According to the plea agreement, Bowyer operated an illegal bookmaking business for at least five years until October 2023. Federal agents raided his San Juan Capistrano home the same month.

Bowyer sat atop an organization with many employees, the agreement said, including casino hosts who referred gamblers and received a portion of the losses that bettors paid. Bowyer sometimes operated the business while he gambled at an unnamed Las Vegas casino — occasionally paying his agents’ commission in chips. Bowyer sometimes collected proceeds at the casino from his gambling business with “payments in casino chips or in cash in envelopes or bags.�

The bookie’s best-known client was Mizuhara, the Japanese-language interpreter and “de facto manager� of Ohtani.

According to Bowyer’s agreement, Mizuhara placed at least 19,000 bets with Bowyer’s gambling business from September 2021 to January 2024. During that period, Mizuhara had winning bets of at least $142 million and losing bets of nearly $183 million — leaving him owing the bookie around $40 million.

The agreement said Bowyer would “bump� Mizuhara — slang for increasing his betting limits — on a regular basis.

A series of text messages between Mizuhara and a person identified in a court filing as “Bookmaker 1,� the operator of an illegal sports book whose details match those of Bowyer’s operation, portray the growing pressure on the interpreter to pay what he owed.

“Hey Ippie, it’s 2 o’clock on Friday,� Bookmaker 1 texted in November 2023. “I don’t know why you’re not returning my calls. I’m here in Newport Beach and I see [Ohtani] walking his dog. I’m just gonna go up and talk to him and ask how I can get in touch with you since you’re not responding? Please call me back immediately.�

The pressure continued to mount in a text message Bookmaker 1 sent Mizuhara in January 2024: “You’re putting me in a position where this is going to get out of control. If I don’t hear from you by the end of the day it’s gonna be out of my hands.�

The money to finance Mizuhara’s gambling, authorities later charged, came through illicit transfers from Ohtani’s bank account.

The Times first reported in March that Ohtani’s representatives had accused Mizuhara of “massive theft� and notified law enforcement. The Dodgers fired Mizuhara and, in April, he was charged with stealing almost $17 million from Ohtani.

Ohtani has denied any knowledge of the gambling. E. Martin Estrada, the U.S. attorney for the Central District of California, said during an April news conference that Ohtani “has been established as victim in this case� and lauded his cooperation with authorities.

Mizuhara pleaded guilty on June 4 to one count of bank fraud and one count of subscribing to a false tax return. He will be sentenced on Oct. 25.

In his plea agreement, Bowyer admitted that in 2022 he reported $607,897 in total income when, in reality, he made more than $4 million. Bowyer owes additional taxes of $1.6 million for that year, not including interest and penalties, according to the U.S. attorney’s office.

As part of the agreement, Bowyer will forfeit $257,923 in U.S. currency and $14,830 in casino chips seized by law enforcement in October 2023.