Democrats on the House oversight committee sent a letter to Chief Justice John Roberts on Thursday demanding to know how the Supreme Court is enforcing ethical standards — and questioning whether the high court is even prepared to do so.

“We write with alarm about the deepening ethics crisis at the Supreme Court of the United States, which is turning into a full-blown legitimacy crisis,” read the letter, signed by ranking member Jamie Raskin (D-Md.) and vice ranking member Alexandria Ocasio-Cortez (D-N.Y.).

“You have repeatedly asked Congress and the American people to trust Justices of the Supreme Court to police their own conduct ... yet, over the past year, revelations by investigative reporters and Senate investigators have established that certain Justices have abused that trust,” they wrote.

Roberts has already declined to meet with Senate lawmakers on the chamber’s powerful judiciary committee to answer for the controversial actions of conservative Justices Clarence Thomas and Samuel Alito.

In the House, where Republicans are in the majority, Democrats concerned about the Supreme Court’s alarming ethical lapses have resorted to sending the court letters and staging events to highlight the issues, such as the roundtable discussion held by Raskin and Ocasio-Cortez last week.

In their letter this week, the duo pointed out how ethical concerns — such as Thomas’ millions in lavish gifts from wealthy friends and Alito’s far-right dog whistles — have only come to light thanks to the work of journalists and other outside investigators, not the court itself.

“This anomalous way of keeping track of ethical transgressions at the Court raises the question of whether the Supreme Court is unable, or perhaps just unwilling, to investigate and police its own conduct to ensure that Justices comply with their statutory and constitutional obligations,” they wrote.

“Justice Alito’s and Justice Thomas’s transparently partisan ideological activity calls into question their impartiality with regard to matters currently pending before the Supreme Court.”

Both Alito and Thomas have refused to recuse themselves from cases in which their impartiality could be called into question, including cases relating to the Jan. 6, 2021, attack on the Capitol.

Raskin and Ocasio-Cortez demanded to know whether the Judicial Conference — the government agency that makes policy recommendations to federal courts — has investigated the justices to ensure compliance with financial disclosure rules. They also asked for specific information about how the court reviews allegations that a justice should recuse themselves from a case, among other questions, and set a deadline of July 5.

The vacations and other perks Thomas has accepted over the years were largely uncovered by ProPublica, a nonprofit journalism outlet. Revelations that controversial flags had been flown outside Alito’s homes in Virginia and New Jersey came to light in reports by The New York Times and The Washington Post in recent weeks.

Earlier this month, Lauren Windsor, an independent journalist, recorded Alito bashing the media and voicing his support for returning America “to a place of godliness” during a dinner reception hosted by the Supreme Court Historical Society. At the dinner, Windsor also recorded Alito’s wife, Martha-Ann Alito, evoking her German heritage to suggest she would retaliate against her critics.