Steve Stockman, a Republican former congressman from Texas, has been convicted of defrauding two conservative mega-donors and funneling their $1.25 million into personal and campaign expenses as part of what prosecutors have described as a “white collar crime spree.”

A jury in federal court in Houston ruled Thursday afternoon that Stockman is guilty of all but one of the 24 felonies he was charged with last March. After about 16 hours of deliberations over three days, the 12-person panel only declined to convict on one of four counts of wire fraud.

Stockman will appeal the verdict, his defense team said.

“Mr. Stockman is keeping his head up and we're looking forward to getting through to the next stage of this," defense attorney Sean Buckley said.

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That verdict puts Stockman — a firebrand conservative who served two nonconsecutive terms in the U.S. House before losing a 2014 challenge to U.S. Sen. John Cornyn, R-Texas — at risk of decades in federal prison. And in the immediate future, it sends him into federal custody, where he will remain pending sentencing in August. U.S. Marshals took him into custody shortly after the verdict was read, over the objections of his lawyers. The prosecution had warned that he might be a “flight risk,” Buckley explained.

Stockman has been on trial in federal court in Houston for nearly a month on corruption charges that include mail and wire fraud, money laundering and violations of federal election law. As he heard the jury’s verdict Thursday, he sat expressionless, according to the Houston Chronicle.

Ryan Patrick, the new U.S. attorney for the Southern District of Texas and the son of Lt. Gov Dan Patrick, was in the courtroom for the verdict.

“When public officials use their office to defraud donors and violate federal law, we will hold them accountable," Patrick said in a statement Thursday afternoon. "Corrupt officials like former congressman Stockman make it harder for the honest ones to do their jobs.”

Stockman was accused of improperly using charitable donations for unrelated efforts, including campaign and personal expenses ranging from a new dishwasher to undercover surveillance of a perceived political rival.

The Houston-area former lawmaker's attorneys have claimed that the pair of conservative mega-donors who gave him that money intended for it to serve as campaign contributions and gave the former lawmaker broad leeway for using it. Prosecutors argued that Stockman promised that money would go to specific purposes — including “educating” voters and renovating a conservative “Freedom House” for interns — and that the former lawmaker used his credibility to mislead donors.

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“There has been so much rhetoric publicly about Congressman Stockman and his political views. We’re in such a politically charged environment that I can’t say I’m surprised by anything,” Buckley said. “But I am disappointed and I don’t think it’s the right result.”

If upheld on appeal, the felony conviction would make Stockman ineligible to seek Texas office. But the U.S. Constitution, which lays out eligibility requirements for federal office, does not exclude convicted felons from seeking election to the U.S. Congress.

Stockman was charged with two former aides, Thomas Dodd and Jason Posey, who both entered guilty pleas and testified against their former boss. The three faced 28 felony charges in total.