Industry experts and lawmakers who spoke at a hearing of the United States Senate Committee on Banking, Housing, and Urban Affairs clashed on how the country should handle digital assets used for illicit purposes.

Speaking remotely in a Thursday hearing on “Understanding the Role of Digital Assets in Illicit Finance,” Michael Chobanian, the founder of Kuna crypto exchange and president of Blockchain Association of Ukraine, called out Binance. He claimed the crypto exchange was “still working with the ruble” and implied the firm was not in compliance with current sanctions against Russia, which has engaged in a military invasion of Ukraine since Feb. 24.

In his written testimony, Chobanian said Kuna had stopped “all support for the Russian ruble” in an effort to support Ukraine and weaken the economy of the nation currently launching ground and air attacks against it. Binance CEO Changpeng Zhao has previously said the exchange followed all sanction rules, but a spokesperson added at the time the firm would not “unilaterally freeze millions of innocent users’ accounts” in Russia.

“To stop Russia in its tracks, and to bring about a more democratic world with personal freedom through cryptocurrency, we appeal to crypto exchanges worldwide, including Binance, to block any interaction with sanctioned individuals until the fall of Putin’s regime and end of aggression against Ukraine,” said the Kuna founder.

Some of the lawmakers in attendance at the hearing pushed back against the idea that cryptocurrencies held by wealthy Russians or Russian President Vladimir Putin could be used to circumvent existing sanctions. Senator Pat Toomey said there was “no evidence of cryptocurrencies being used by Russia to evade sanctions in any significant way,” adding their traceability makes digital assets risky for criminals to use for any illicit transactions.

Discussions on Russia and Ukraine at the hearing represented two possible extremes of use cases of crypto. On the one hand, some lawmakers implied a country like Russia could potentially use the technology to bypass sanctions as was the case for Venezuela, Iran and North Korea. On the other hand, crypto transactions allowed good Samaritans to send funds to Ukrainians in need of food and military equipment for defense quickly — Chobanian said it only took “about ten minutes” to set up crypto donations for Ukraine, while the National Bank of Ukraine took roughly ten days to arrange transfers in fiat.

Ransomware attacks were also on lawmakers’ lips, given the seeming affinity of criminals for demanding payment in cryptocurrencies, including Bitcoin (BTC), to prevent the release of sensitive information or restore access to critical systems. However, according to Jonathan Levin, co-founder and chief strategy officer of analytics firm Chainalysis, wallet addresses associated with illicit activity represented “just 0.15% of digital asset transaction volume in 2021,” which was also an all-time high value. Authorities in the United States were also able to track and seize many of the funds from the ransomware attack on the Colonial Pipeline in May 2021.

“Overattributing cybercrime to cryptocurrency misses critical causes and preventive measures which can be taken,” said Michael Mosier, former acting director of the Financial Crimes Enforcement Network.

Lawmakers and industry leaders have previously criticized government officials for not providing sufficient regulatory clarity in the crypto space. Republican Senator Cynthis Lummis said in December that she was planning to introduce legislation providing a comprehensive framework for crypto, including providing regulatory clarity on stablecoins and guidelines for regulators to determine which tokens would be categorized as different asset classes. 

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The Wyoming Senator did not mention her bill at the hearing and has not referenced it on her social media accounts since March 9, shortly after U.S. President Joe Biden signed an executive order which will establish a regulatory framework for crypto. However, Democratic Senator Elizabeth Warren said on Thursday she had introduced a bill announced earlier this month aimed at cracking down on crypto as a way to avoid economic sanctions.

“The [best] thing Congress can do is provide clarity,” said Mosier. “There are a lot of crypto firms out there that would like to be certain in that they are complying with the law, and I think there’s a lot of debate, particularly across the SEC and the CFTC, about what exactly is needed to be in compliance.”