United States Senators Elizabeth Warren and Charles Grassley have sent a letter to Commodity Futures Trading Commission (CFTC) chair Rostin Behnam asking for an accounting of Behnam’s contacts with former FTX CEO Sam Bankman-Fried before the cryptocurrency exchange’s collapse. The writers say they want to “renew requests” for that information and cite a letter addressed to Behnam and others by Sen. Josh Hawley.

Warren and Grassley, who represent opposite ends of the U.S. political spectrum, reminded Behnam that he told a Senate Agriculture Committee hearing in December that “My team and I met with Mr. Bankman-Fried and his team [...] over the past 14 months, we met 10 times in the CFTC office at their request.”

Behnam, who was the sole witness speaking at the hearing, used the hearing as a platform to appeal for more authority, saying, “Without new authority for the CFTC, there will remain gaps in a federal regulatory framework, even if other regulators act within their existing authority.” Warren and Grassley wrote in a letter dated April 12:

“Safeguarding the savings and retirements of Americans requires Congress and market regulators like the CFTC to determine how this multi-billion-dollar crime was allowed to happen.”

Behnam also noted that CFTC-regulated and FTX-owned LedgerX was not part of the FTX collapse and remained operational.

The senators are demanding accounts of all meetings, phone calls, written correspondence and conversations between Behnam or CFTC staff and Bankman-Fried, FTX, Alameda or associated executives. In addition, they ask for a “timeline of CFTC’s knowledge of the fraud committed, including but not limited to a description of any proposed or ongoing investigations into those parties.”

According to the letter, the senators want to “understand the nature of your [Behnam’s] repeated correspondence with Mr. Bankman-Fried” before knowledge of his crimes became public.

Related: CFTC Chairman Rostin Behnam cites LedgerX as success story amid FTX collapse

Republican Hawley wrote to Behnam, Attorney General Merrick Garland and Securities and Exchange Commission (SEC) Chairman Gary Gensler in November asking if their agencies had begun investigations into FTX or Alameda before their collapse or entered into confidential settlements with the companies or their executives.

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