Congress is trying to force the U.S. Supreme Court to hold justices accountable to standards of ethics and good behavior in this politically-polarized "MeToo" era.
The court is currently the only branch of government without an ethical code of conduct or an independent enforcement system to address allegations of wrongdoing.
The House of Representatives on Friday passed a sweeping government transparency and ethics reform bill that requires the federal judiciary to "issue a code of conduct which applies to each justice… of the United States."
While the Supreme Court justices are said to consult the canon of formal guidelines applied to lower court judges to ensure integrity, independence and impartiality – they are not bound by them and are not supervised by a third party.
Under the Constitution, justices can serve as long as they exhibit "good behavior" and can only be removed for "treason, bribery or other high crimes and misdemeanors."
"Episodes of the last two decades have made clear that the Supreme Court’s consultation of the code is not sufficient," Sarah Turberville, director of the Constitution Project at the nonpartisan independent watchdog group Project on Government Oversight, told lawmakers earlier this year.
One recent example watchdogs cite: Justice Brett Kavanaugh’s confirmation hearing testimony. The newest member of the court has been accused of harming the panel’s image of impartiality with combative, political statements.
"What goes around comes around," then-Judge Kavanaugh said last year during an impassioned tirade against what he called a Democratic conspiracy to smear him with sexual assault allegations.
Justice Ruth Bader Ginsburg was sharply criticized in 2016 and later apologized for publicly disparaging Donald Trump in the midst of the presidential campaign.
In 2004, late Justice Antonin Scalia was seen on a hunting trip with then Vice President Dick Cheney weeks before the court was to hear a case against Cheney.
"In several notable instances, the conduct of a Supreme Court justice clearly would have violated one or more of the code’s canons of judicial conduct," Tuberville said. Regardless, she added, "the perception of impartiality is just as important to the court’s legitimacy."
A Supreme Court spokeswoman did not respond to ABC News’ request for comment on passage of the House bill.
There are signs the court is feeling pressure to act.
Justice Elena Kagan told lawmakers Thursday during a hearing on the Supreme Court’s budget that Chief Justice John Roberts "is studying the question of whether to have a code of judicial conduct that’s applicable only to the United States Supreme Court."
Kagan added, however, that the justices have "reservations" about adopting the same rules that apply to all other federal judges.
The code of conduct developed by a panel of senior federal judges, including Chief Justice Roberts, mandates that all members of the federal bench maintain integrity and independence; avoid even the appearance of impropriety; act fairly and impartially; and refrain from political activities.
Justice Samuel Alito told the budget hearing Thursday that the high court has not had to grapple with harassment allegations like those that have surfaced at other levels of government and in the courts.
"I’m not aware of problems on the Supreme Court itself," Alito said. "All of the justices are aware of this potential problem and were it to come to our attention that there were any problems along these lines regarding or involving anybody who works across in the Supreme Court building, we would not sit back. We would take action that’s appropriate," he said.
Ethics advocates say the justices should not be allowed to police themselves and that the court needs to establish clear standards and systems for accountability.
Federal law already requires judges, including justices of the Supreme Court, to recuse themselves from "in any proceeding in which their impartiality might reasonably be questioned." They must also submit annual financial disclosures to ensure no conflicts of interest.
Legislation requiring a code of conduct at the Supreme Court has long enjoyed widespread support from Democrats and Republicans but never been enacted. The wide-ranging House Democrats ethics bill that passed on Friday, however, will almost certainly not be considered by the Republican-controlled Senate.
Attempts by Congress to police the court have also raised concerns about separation of powers. The Constitution established the Supreme Court as an independent branch of government and left to Congress to create and supervise the lower court system.
"Chief Justice Roberts himself has hinted that attempts by Congress to prescribe particular ethics standards for the Supreme Court may violate the separation of powers," said ABC News Supreme Court analyst Kate Shaw. "That said, because this bill gives the Court the power to draft its own ethics rules, I'm not sure the separation-of-powers concerns are very serious."
Shaw said the justices are also likely concerned about the impact of more frequent recusals might have on the Supreme Court because there are no "alternate" Supreme Court justices as there are in the lower courts, and it takes a quorum of six to decide a case.
"Ratcheting up recusal standards might lead to the Court being unable to decide particular cases at all," Shaw said. "The Supreme Court could avoid all of this debate, however, by moving to adopt a code without congressional action. If enough public pressure builds around this issue, I think that's a real possibility."