Federal prosecutors have signaled that they will file additional criminal charges against a former south King County elected official, who resigned after a KING 5 investigation.

In a motion filed Nov. 19 in U.S. District Court, Assistant United States Attorney Justin Arnold wrote that the government is seeking charges of “…additional mail and wire fraud counts, money laundering counts, aggravated identity theft counts, and possibly tax counts.”

Allan “Benny” Thomas and his wife JoAnn currently face a single count of mail fraud.

The FBI arrested the Thomases on September 30 on allegations that they diverted nearly $500,000 in tax money to their private bank account.

Thomas was the 30-year commissioner of King County Drainage District No. 5 in Enumclaw until a KING 5 investigation in April revealed the improprieties.

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The court documents also provide new insight into an FBI raid at Thomas’ 150-acre dairy farm before he was arrested. Those records say agents collected 17,000 pages of records, including seven to eight boxes of documents seized from the Thomas home and 500 GB of data.

Prosecutors and defense attorneys have both asked the judge to delay trial until May 2020 so the defense team will have time to review the extensive documentation.

The court documents do not further explain how the Thomases may have laundered money or committed identity theft, two of the additional charges that are under consideration.

As the elected commissioner of King County Drainage District No. 5, Thomas was responsible for governing tax collection and maintenance of 18 miles of trenches that prevented flooding in and around Enumclaw.

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Using county records and documents and video from an Enumclaw Police Department investigation, the KING 5 investigators showed how Thomas allegedly stole tax money collected over at least a seven-year period from the 600 property owners in the district.

A subsequent state audit showed that Thomas spent the money on feed for his cows and other farm-related expenses.

Thomas denied any wrongdoing to KING 5.

The FBI opened a public corruption investigation soon after.