A Southern California bookmaker who took many sports bets from Shohei Ohtani’s former interpreter admitted in court on Friday to running an illegal gambling operation.
Mathew Bowyer, 49, pleaded guilty to operating the illegal betting business, money laundering, and filing a false tax return in federal court in Santa Ana. He is scheduled to be sentenced on February 7.
Bowyer told the judge, “I was running an illegal gambling operation, laundering money through other people’s bank accounts.”
Federal prosecutors did not comment after the hearing.
Prosecutors said Bowyer had been running the illegal gambling business for at least five years in Southern California and Las Vegas. He accepted bets from over 700 people, including Ippei Mizuhara, Ohtani’s former interpreter.
Running an unlicensed gambling business is a federal crime. In California, sports gambling is illegal, even though 38 states and the District of Columbia permit some form of it.
Mizuhara admitted to bank and tax fraud for stealing nearly $17 million from Ohtani’s bank account. Mizuhara, who used to work for the Los Angeles Angels before joining the Los Angeles Dodgers, is set to be sentenced in October.
Federal investigators found that Mizuhara placed about 19,000 bets between September 2021 and January 2024. Although his total winnings were over $142 million, which he deposited into his own account, his losses amounted to around $183 million, resulting in a net loss of nearly $41 million.
There was no evidence that Mizuhara bet on baseball. Prosecutors said there was no proof that Ohtani was involved in or aware of Mizuhara’s gambling. Ohtani cooperated with the investigation and is considered a victim.
Diane Bass, Bowyer’s attorney, mentioned that Bowyer never had any contact with Ohtani.
She believes Bowyer’s sentencing could range from 30 to 37 months, based on federal guidelines. However, prosecutors stated that the maximum possible prison sentence for these crimes is 18 years.
“Mr. Bowyer is very relieved to finally be able to accept responsibility for his conduct,” Bass told reporters outside the courthouse after the hearing. “He is looking forward to receiving his sentence so that he can put this chapter behind him and he and his family can get on with their lives.”
Federal prosecutors mentioned that Bowyer’s other clients included a professional baseball player from a Southern California team and a former minor league player. Neither of these individuals was named in court documents.
Bowyer’s guilty pleas add to this year’s sports betting scandals, which have included a lifetime ban for a Major League Baseball player for the first time since Pete Rose was banned in 1989.
In June, the league banned San Diego Padres infielder Tucupita Marcano for life and suspended four other players for betting on baseball legally. Marcano became the first active player in a century to receive a lifetime ban for gambling.
Rose agreed to his ban in 1989 after it was discovered that he had placed multiple bets on the Cincinnati Reds to win between 1985 and 1987 while playing for and managing the team.
MLB’s gambling policy prohibits players and team staff from betting on baseball, even legally. The league also bans bets on other sports with illegal or offshore bookmakers. The penalty for violating this policy is determined by the commissioner’s office.
In Mizuhara’s case, Bowyer was not named directly in the criminal complaint but was mentioned repeatedly as “Bookmaker 1.” Federal prosecutors did not identify him, but Bass confirmed that this term referred to her client.
Court documents show that Mizuhara and Bowyer had frequent communication, ranging from friendly messages—such as Bowyer’s “Merry Christmas” greeting in early December 2022—to threatening messages when Mizuhara was late in paying his debts.
At one point, when Bowyer could not reach Mizuhara, he threatened to approach Ohtani, who was referred to as “Victim A” in the court filings.
“Hey Ippie, it’s 2 o’clock on Friday. I don’t know why you’re not returning my calls. I’m here in Newport Beach and I see (Victim A) walking his dog,” the bookmaker wrote to Mizuhara on November 17, 2023. “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.”
