Sam Bankman-Fried, who has long denied stealing from customers of his cryptocurrency exchange FTX, on Monday asked a US judge to throw out criminal charges against him over the platform's collapse.
In a filing in Manhattan federal court, Mr Bankman-Fried's lawyers said many cryptocurrency exchanges collapsed during a broad market crash in 2022, and that prosecutors hastily charged their client in a “rush to judgment”.
“Rather than wait for traditional civil and regulatory processes following their ordinary course to address the situation, the government jumped in with both feet, improperly seeking to turn these civil and regulatory issues into federal crimes,” his lawyers wrote.
Mr Bankman-Fried, 31, a former billionaire, has largely been confined to his parents' home since his December arrest in the Bahamas, where he had lived and where FTX was based.
He was extradited to the US about a week after his arrest.
FTX imploded after a flurry of customer withdrawals triggered by reports that it had commingled assets with Alameda Research, Mr Bankman-Fried's cryptocurrency-focused hedge fund.
Federal prosecutors in Manhattan said Mr Bankman-Fried stole billions of dollars in FTX customer funds to plug losses at Alameda, buy property and make political contributions through an illegal straw-donor scheme.
They have also charged him with bribing Chinese officials.
In court papers on Monday, Mr Bankman-Fried's lawyers said the campaign finance charge should be dismissed because it was not included on the surrender warrant signed by the Foreign Minister of the Bahamas before their client's extradition.
They also said other charges, including the bribery accusation, were improperly brought after he was extradited.
Under an extradition treaty between the US and the Bahamas, Mr Bankman-Fried may only be tried and punished for charges he faced at the time of his extradition, unless the Bahamas government consents to the new charges.
Prosecutors have until May 29 to respond to Mr Bankman-Fried's dismissal request, and US district judge Lewis Kaplan will hear arguments on June 15.
Mr Bankman-Fried rode a boom in Bitcoin and other digital assets to an estimated net worth of $26.5 billion, according to Forbes magazine.
He became an influential donor to US political and philanthropic causes until his fortune largely evaporated when FTX collapsed in November.
The Massachusetts Institute of Technology graduate has pleaded not guilty to 13 counts of fraud and conspiracy.
He has acknowledged that FTX had inadequate risk management but denies stealing funds, and has sought to distance himself from the cryptocurrency exchange's day-to-day operations.
Three one-time close associates — former Alameda co-chief executive Caroline Ellison, former FTX technology chief Gary Wang and former FTX engineering chief Nishad Singh — have all pleaded guilty and agreed to co-operate with prosecutors.
In pleading guilty, Mr Singh admitted to making political donations in his own name that were funded in part by transfers from Alameda.
However, Mr Bankman-Fried's lawyers said on Monday that the donations made by Mr Singh, referred to as CC-1 in prosecutors' charging documents against their client, did not actually breach election laws.
“The campaign finance allegations reveal, yet again, the consequences of the government's rush to indict Mr Bankman-Fried,” his lawyers wrote.
Mr Bankman-Fried's trial is set for October 2.
His parents, who live in Palo Alto, California, are Stanford University law professors and co-signed his $250 million bond.
Mr Bankman-Fried has limited access to technology, after prosecutors warned he might tamper with witnesses.
