Senator Richard Blumenthal, the ranking Democrat on the Senate Permanent Subcommittee on Investigations, has opened a fresh inquiry into Tether, sending letters to the stablecoin company and to Nxum Group, the consulting firm co-founded by former White House crypto adviser Bo Hines with his father and another partner.
The letters, sent Thursday, seek details of payments that the Wall Street Journal reported Nxum received for consulting work while Hines was still advising President Donald Trump's administration on crypto policy, including on stablecoin issuers significant to Tether. The Journal reported last week that Nxum took millions during that period.
In his letter to Tether CEO Paolo Ardoino, Blumenthal wrote: "The highly unusual terms and nature of Tether's business relationship with both Nxum and Bo Hines raise alarming ethical and legal concerns, indicating that Tether was likely well aware of the illegality and impropriety of issuing payments to a current White House official with such a direct role in shaping cryptocurrency legislation that was instrumental to its business."
Tether said in a statement: "Tether is aware of the allegations reported in The Wall Street Journal that form the basis of Senator Blumenthal's letter. External counsel previously conducted an in-depth internal investigation into the matter, which found no evidence of wrongdoing."
CoinDesk earlier reported that Nxum, which had little track record in politics, made millions as the main campaign-advertising provider for a political action committee associated with Tether. Nxum has since hired Harry Jung, another former White House crypto adviser, and the White House crypto office has gone vacant after the departure of Patrick Witt, who had replaced Hines as its executive director.
The inquiry adds to a series of Tether probes by Blumenthal, who has also examined the stablecoin issuer's reported financial connections to Iran and its relationship with U.S. financial partner Cantor Fitzgerald. Ardoino criticized the senator's work this week, saying Blumenthal ignored important information and released his report to the press before giving the company a chance to respond.
If Democrats win control of the Senate, Blumenthal would likely chair the investigations subcommittee, gaining significantly greater powers to subpoena and set the agenda. Prediction market Kalshi currently gives Democrats a 69 percent chance of taking the chamber.