The uproar over unfair trading practices came after Robinhood and other brokers restricted trading in some stocks last week as volatility soared and frenetic trading from both individual investors and Wall Street hedge funds took stock prices on a wild ride. Individual investors said the restrictions prevented them from being able to participate at crucial times when stocks were surging, and at least 30 lawsuits across the country were filed against Robinhood by irate retail investors. Robinhood did not respond to requests for comment this week. That prompted U.S. Treasury Secretary Janet Yellen to call a meeting on Thursday with top regulators at the Securities Exchange Commission (SEC), Commodity Futures Trading Commission (CFTC), and Federal Reserve Board to discuss what happened last week. By the end of the meeting, they decided the “core infrastructure” of the markets was “resilient” but agreed there had to be further review of Wall Street’s operations to make sure they are fair, investors are protected, and markets are efficient, according to an email statement from the Treasury. Even though Robinhood removed all trading restrictions on Friday, the Treasury said in the email statement that the SEC and CFTC would continue to review trading practices and that the SEC will release a “timely study of the events.” The House Financial Services Committee also plans to have hearings on what transpired on Feb. 18. “This hearing is going to be educational, it’s going to be a learning experience for everybody,” California representative Maxine Waters, chairwoman of the committee, said in an interview with news platform Cheddar on Wednesday. Waters said the committee expects to hear from Robinhood CEO Vlad Tenev, as well as Keith Gill—the person on Reddit whom Waters said supposedly started the trading mania—and, possibly, some hedge funds. Among the questions Waters said she wants answered is how Robinhood makes its money if no commissions are charged to its users. Tenev is expected to testify before the House Financial Services Committee on Feb. 18, according to Politico, citing unnamed insiders familiar with the matter.