(CNN)A federal judge in New York rejected Lev Parnas' motion to dismiss fraud and campaign finances charges, finding an argument that he was prosecuted to block him from cooperating against former President Donald Trump is "not just speculative, but implausible."
Parnas, a former associate of Rudy Giuliani, argued that he was arrested and charged in late 2019 to stop him from cooperating with the House impeachment investigation into Trump's activities in Ukraine.
Parnas and Igor Fruman worked with Guiliani on his efforts to dig up dirt on then-Trump rival Joe Biden and push for Ukraine to announce an investigation into Biden and his son Hunter.
"But the theorizing of Twitters users, and Parnas's own speculation, do not constitute evidence of an improperly motivated prosecution," Judge Paul Oetken wrote, noting that Parnas initially did not cooperate with the impeachment inquiry. "To accept Parnas's conspiracy theory, the Government would have to have known that, one day in the future, Parnas would change his mind and decide to cooperate with the Congressional demand."
The judge noted that the government didn't object to Parnas' television appearances and media interviews. The judge also denied Parnas' request to seek records from the government to pursue the theory.
Parnas, Fruman and Andrey Kukushkin are set to go to trial in October on three different alleged schemes. All three men have pleaded not guilty to the charges.
Each of the defendants filed motions to separate their trials from the others.
The judge granted only one of those requests and agreed to sever the charges against Parnas for allegedly defrauding investors in a company called Fraud Guarantee, where Parnas is the only defendant.
The three men will all go to trial together on alleged schemes they used straw donors and foreign donors to make campaign donations to US elections.
"Neither the proffered evidence nor the nature of the alleged schemes, which are relatively straightforward, supports a conclusion that a joint trial would be substantially prejudicial," the judge wrote.
The judge denied the defendants' request for a court hearing to discuss any materials obtained in the government search warrants executed on Giuliani and lawyer Victoria Toensing's electronic devices in April.
The judge said any relevant material or communications involving the defendants are "likely to have already been produced from Parnas's and Fruman's own devices."