Sen. John Cornyn, R-Texas, blasted Senate Judiciary Committee Chairman Dick Durbin, D-Ill., during a hearing Thursday that ended in Democrats subpoenaing Republican donor Harlan Crow and conservative judicial activist Leonard Leo.

The Senate Judiciary Committee voted to subpoena Crow and Leo after consideration of several judicial nominees. In his opening remarks, Durbin said the subpoenas are “key pieces of our legislative effort to establish an effective code of conduct” for the Supreme Court.

The hearing contained several contentious moments, with Republican committee members warning of precedents they said Democrats were setting with their actions. Cornyn fired directly at Durbin after allegedly not allowing Republicans to speak.

“Mr. Chairman, you just destroyed one of the most important committees in the United States Senate,” Cornyn said. “And you set a precedent, which will be repeated every time one party or the other takes advantage and takes the low road. It sets a precedent that will then become the norm.”

“Congratulations on destroying the United States Senate Judiciary Committee,” he said.

Democrats have long sought to cross-examine Crow and Leo, the vice president of the Federal Society, as part of an ethics probe into allegations that Justices Clarence Thomas and Samuel Alito failed to disclose luxury vacations paid for by the conservatives, who are also their friends.

Thursday’s vote comes weeks after the Supreme Court issued a new “Code of Conduct” in response to months of heightened scrutiny from Democrat lawmakers and news reports. Durbin said the self-imposed ethics code “falls far short” and urged Congress to impose more stringent standards on the high court.

Republicans have panned Democrat-sponsored legislation, the Supreme Court Ethics, Recusal and Transparency (SCERT) Act, as a “court-killing machine” that would “destroy the legitimacy of the conservative court.” They argue that federal judges are already bound to an ethics code, including Supreme Court justices, and that an act of Congress on the judiciary would unconstitutionally infringe on a separate and co-equal branch of government.

For decades, Leo has been a part of the Federalist Society, which liberal activists have criticized for its involvement in helping advise and lobby former President Trump through the nominations of Supreme Court Justices Gorsuch, Brett Kavanaugh and Amy Coney Barrett.

And following the hearing, Leo told Fox News he would not cooperate with the Senate Democrats.

“Senate Judiciary Committee Democrats have been destroying the Supreme Court; now they are destroying the Senate,” Leo said. “I will not cooperate with this unlawful campaign of political retribution.”

Leo has also come under the microscope of Washington, D.C.’s, Democrat attorney general, Brian Schwalb, who launched an investigation into Leo’s network this past summer.

Schwalb’s office faced criticism for targeting Leo while ignoring a similar liberal dark money network overseen by the Arabella Advisors consulting firm.

However, after the criticism, Schwalb’s office also opened a probe into the Arabella Advisors-managed network.