Federal prosecutors: ‘Aggressive’ attempts to undermine bribery case against Sheng Thao, Duongs ring ‘hollow’

OAKLAND — Months before speaking to their controversial star informant, federal investigators had already amassed a trove of eyebrow-raising texts, Apple notes and other data against former Oakland Mayor Sheng Thao and the men accused of bribing her for political favors, according to a new court document filed this week.

The existence of that evidence — obtained by federal authorities via subpoenas for iCloud data, cell phone logs and email accounts — sheds fresh light on the sprawling corruption case that FBI agents and U.S. attorneys have been building since early 2023. It was detailed in a new filing Wednesday by federal prosecutors, which sought to dispel the notion that their case had been built on the words of a man with significant credibility concerns.

Federal prosecutors instead argued that the informant’s help amounted to little more than window dressing to an otherwise provable case.

“The government had been investigating defendants’ bribery scheme for over a year before interviewing Co-Conspirator 1,” federal prosecutors wrote.

The filing comes amid claims by attorneys for Thao and her three co-defendants that key federal warrants used to search their homes — and any evidence collected there — should be tossed. In a flurry of motions last year, the quartet blasted the government’s case as being propped up by nothing more than the “self-serving spin” of an unnamed co-conspirator with a “shockingly long history of criminal charges and civil disputes.”

Those concerns appeared to be centered on former two-time Oakland City Council candidate Mario Juarez, who has been referred to in court filings only as Co-Conspirator 1 and is widely believed to be cooperating with federal prosecutors in the case against Thao, her romantic partner, Andre Jones, and the father-and-son business duo of David and Andy Duong.

The defendants cited a litany of lawsuits, criminal investigations and allegations of fraud against the government’s star informant. They also suggested that federal investigators hid much of that man’s past from judges who signed off on the search warrants, meaning evidence collected during raids on their houses in June 2024 should be thrown out.

“Three decades’ worth of public records, press stories, past federal and state criminal investigations, and inconsistent statements to law enforcement collectively show what should have been obvious to investigators in this case: the government’s key witness … lacks all credibility,” wrote Andy Duong’s attorneys in an early December filing.

Federal prosecutors, however, suggested this week that those complaints by Thao and her trio of co-defendants ring “hollow.” Instead, the quartet’s reasonings are rife with “significant hyperbole and aggressive language,” and “misstate and mischaracterize the record and applicable case law,” the government’s filing said.

“Here, even if the omitted information rendered Co-Conspirator 1’s statements completely untrustworthy such that they could not be considered in any way (which it does not), the remaining evidence detailed in the affidavits supports a finding of probable cause independent of his statements to law enforcement,” government prosecutors wrote.

Federal prosecutors painted a far different picture — instead suggesting they already had a stacked case against Thao, Jones and the Duongs before even speaking to the unidentified co-conspirator. They have even mentioned that the man appears to be “motivated by revenge against the Duongs and a desire to obtain protection from law enforcement” from the family,” while holding out “hope of obtaining some form of leniency in exchange.”

Federal officials say they first started investigating corruption in the East Bay in late 2022, after Juarez allegedly failed to pay for mailers during that fall’s mayoral election that had targeted Thao’s political opponents. Juarez later faced state charges for those bounced checks, though the case was ultimately dismissed.

By early 2023, federal investigators had turned their attention to Thao, Jones and the Duongs, federal investigators say. And by early 2024, prosecutors had amassed “a significant amount of documentary evidence” against them, the filing claimed.

The case appeared to gain steam in the first half of 2024. Between February and May of that year, federal authorities obtained four separate search warrants from two magistrate judges for a host of messages and digital data.

One warrant targeted the iCloud accounts of Thao, Jones and Andy Duong, while another sought cell phone records for all four defendants and Co-Conspirator 1, this week’s filing said. A subsequent warrant sought data in David Duong’s iCloud account, while a fourth sought email sent and received by Thao and the Duongs.

Only afterward, on June 6, 2024, did investigators first speak to the unidentified co-conspirator, the filing said. Prosecutors framed their discussion with him as merely necessary for “context and completeness.”

Two weeks later, federal authorities raided the houses of Thao and the Duongs, casting a public spotlight on an investigation that culminated in a series of grand jury indictments in January 2025 on conspiracy, fraud and bribery charges.

Thao is accused of accepting bribes from Andy Duong and his father, David, in the form of political favors and a $95,000 no-show job for Jones. In return, prosecutors say Thao promised to secure lucrative city contracts for a fledgling housing company co-founded by David Duong and the co-conspirator, as well as for the Duongs’ recycling business, California Waste Solutions.

The four defendants, who have all plead not guilty, are scheduled to appear for trial on Oct. 19.

In the meantime, David Duong has kept a busy schedule — securing permission from federal judges to travel to Donald Trump’s inauguration last year and Vietnam for business interest — while appearing intent on restoring his family’s reputation both inside and out of the courtroom.

Earlier this month, the Duongs premiered a new documentary, “The King of Trash,” that traces the rise of their trash-collecting empire in Vietnam and California. The film, which does not mention the ongoing legal case, paints a portrait of David Duong as a hard-striving businessman who built up California Waste Solutions, which has city contracts to pick up curbside recycling in Oakland and San Jose, after escaping Vietnam amid a communist takeover in the mid-1970s.

A fancy premiere at a Jack London Square movie theater gave no impression that David Duong — dressed in a full suit and posing for red-carpet photos with his family — is facing severe federal prison time. Andy Duong, who attended the premiere, is not featured in the film.

“We trust the American justice system,” Duong told reporters at the gala. “I’m sure that I didn’t do anything wrong, and I just hope for that day (when my) name is cleared.”

Jakob Rodgers is a senior breaking news reporter. Call, text or send him an encrypted message via Signal at 510-390-2351, or email him at jrodgers@bayareanewsgroup.com.