“This abuse of the revolving door is appalling, revealing that the crypto industry is spending millions to give itself a veneer of legitimacy while fighting tooth and nail to stonewall common sense rules designed to restrict the use of crypto for terror financing — rules that could cut into crypto company profits,” she said. “It also reveals significant gaps in the nation’s ethics laws.”

The requests, which crypto leaders immediately criticized, marked an escalation in Warren’s push for an industry crackdown. She has been building bipartisan support for legislation that would impose new anti-money laundering safeguards on the crypto market and she led more than 100 lawmakers to ask the Biden administration to intervene after the Oct. 7 attacks in Israel.

Crypto firms have tried to argue that the Hamas funding concerns have been exaggerated and that the industry has recruited former officials to bolster its legal compliance. It’s also not alone: Traditional banks and financial firms have long employed ex-officials and policymakers in their lobbying and other operations.

Blockchain Association CEO Kristin Smith said in response to Warren’s letter that “people are drawn to work in the crypto industry because they value freedom, sovereignty of the individual, and permissionless innovation.” Coinbase head of U.S. policy Kara Calvert said the national security and law enforcement experts that the crypto exchange employs “do not deserve to be maligned as they work to keep our nation strong and safe.”

“Engaging like-minded experts to advocate against legislative proposals that one sincerely believes are unconstitutional and detrimental to the nation’s welfare does not constitute ‘undermining bipartisan efforts in Congress,’” Coin Center Executive Director Jerry Brito said, quoting Warren’s letter. “Rather, it is the exercise of the fundamental right to freely associate and petition the government.”