Executives from eight major cryptocurrency companies were called to testify before a U.S. Congressional committee on December 8.

Witnesses called to appear include Coinbase’s Alesia Haas, Circle’s Jeremy Allaire, and Bitfury’s Brian Brooks.

It will be the first time that companies representing the controversial sector have been questioned in this way.

US politicians across the political spectrum have called for greater scrutiny of cryptocurrencies.

Democratic left-wing Elizabeth Warren called for stricter industry regulation, and Donald Trump described cryptocurrencies as “a scam.”

Bitfury’s Mr. Brooks was previously a major banking regulator under the Trump administration and had a role in shaping cryptocurrency-related policies.

Cryptocurrencies are not currencies in the traditional sense, although they can sometimes be used to make payments. They are stored online in a “digital wallet” and act more like investment vehicles or securities, often with a high degree of volatility.

The anonymity of payment using cryptocurrencies means that they have been favored for criminal activities such as drug dealing and ransomware attacks. However, their supporters argue that the view that they are primarily aimed at circumventing the law is outdated and that innovation in this area offers enormous potential.

Countries around the world have taken radically different approaches to cryptocurrencies.

China has outlawed cryptocurrency transactions, a move India looks set to follow. Many other central banks watch the sector cautiously and discuss regulation.

However, El Salvador recently declared that Bitcoin – the most widely used cryptocurrency – is legal tender and its president plans to build a Bitcoin city at the base of a volcano, with the cryptocurrency being used to fund the project.

In the United States, in addition to many private citizens who hold cryptocurrencies, states and municipalities have begun to play with plans to integrate them into their operations.

The mayor of Miami and the elected mayor of New York have the ambition to make their cities centers for the cryptocurrency business.

According to the commission’s announcement, the hearing before the US House Financial Services Committee will focus on the “challenges and benefits of financial innovation.”

The other CEOs asked to appear are Sam Bankman-Fried of FTX Trading, Chad Cascarilla of Paxos and Dennelle Dixon of the Stellar Development Foundation.