Several members of Congress wanted to make sure the White House commission on the Supreme Court heard their views ahead of the first public hearing Wednesday on the debate over expanding the court beyond its current nine members and other potential overhauls.

Texas Republican Sen. Ted Cruz and Republican Rep. Dusty Johnson of South Dakota submitted a comment to the commission that Congress has exclusive authority to change the Supreme Court’s structure.

The letter also seeks “to remind you of the growing congressional momentum” for their bills for a constitutional amendment to keep the court at nine justices, with 18 senators and 173 representatives as co-sponsors.

“Despite the President’s inability to alter the Supreme Court, President Biden established your commission to pacify the far left,” Cruz and Johnson wrote.

Those proposed amendments respond to calls from some liberal advocacy groups and members of Congress to expand the court.

Massachusetts Democratic Sen. Edward J. Markey and three Democratic members of the House — Judiciary Chairman Jerrold Nadler and Rep. Mondaire Jones, both of New York, and Georgia Rep. Hank Johnson — have introduced a bill to increase the number of justices from nine to 13.

Speaker Nancy Pelosi has cast serious doubts on the chances of the bill, pointing instead to the work of the commission that will examine high-profile ideas such as whether justices should have term limits instead of life tenure on the Supreme Court.

Senate Majority Leader Charles E. Schumer sent the commission the series of reports the Democratic Policy and Communications Committee published in May 2020 titled “Captured Courts: The GOP’s Big Money Assault on The Constitution, Our Independent Judiciary, and the Rule of Law.”

A bill that Rhode Island Democratic Sen. Sheldon Whitehouse championed and Republicans opposed, which has a provision to require advocacy groups to disclose donors if they run ads around judicial nomination fights, is in Democrats’ elections, campaign finance and ethics overhaul bill that stalled in the Senate during a procedural vote this month.

“Among many other serious problems, this big-money assault on our courts has resulted in voters waiting for hours in long lines to exercise their right to vote; special interests flooding our airwaves with political ads; worker discrimination cases being thrown out of court; communities being left powerless to regulate gun violence; polluters enabled to pollute our air and water without consequence; and access to health care under constant attack,” Schumer wrote. “I believe that the problems identified in these reports should inform the work of the Commission, and I ask that you share the reports with all of your fellow commissioners.”

Whitehouse, in a letter to the commission with fellow Democratic Sens. Mazie K. Hirono of Hawaii and Richard Blumenthal of Connecticut, as well as Hank Johnson, suggested a dozen areas the commission should study that includes the issue of dark money influence on the Supreme Court.

“This set of interwoven problems connected by secret funding is likely the primary driving force behind the degradation of confidence that necessitated this Commission’s formation,” the Democratic members wrote.

That includes the role of dark money nonprofit groups that have held sway over the judicial confirmation process, whether Congress should have a role in cleaning up Supreme Court decisions that rely on factual errors, disclosure requirements for outside groups that file briefs in a Supreme Court case and the disclosure requirements for justices.

Earlier this month, Whitehouse and Louisiana Republican Sen. John Kennedy asked the Justice Department for travel records of the justices as part of a broader congressional look at financial disclosure standards for the receipt of gifts, travel and other financial gains by senior government officials.

The commission’s public meeting, conducted virtually online, will last all day. The commission will hear four panels with five people on each, tackling topics of Supreme Court reform, the court’s role in the constitutional system, how the court selects cases and transparency at the court.

One witness, Amy Howe of SCOTUSblog, will testify that the justices should continue with live audio of oral arguments when they return to in-person arguments in the courtroom.

After the onset of the pandemic, the Supreme Court held arguments over the telephone that were broadcast online and on television by C-SPAN and other outlets. But it is unclear if the Supreme Court will continue to allow livestreams of oral arguments when the next term starts in October.

Last week, the Senate Judiciary Committee advanced a bipartisan bill that would require the Supreme Court to permit television coverage of all open sessions in almost all cases. Supreme Court justices have long resisted calls for more audio and video access to its work.

The commission also intends to hold panels at its July meeting, tentatively planned for July 20.