It’s been over 30 years since Justice Clarence Thomas was confirmed to the US Supreme Court seat once held by the great Thurgood Marshall and it’s safe to say that his reputation — which was poor to start with — has only got worse.

What are we supposed to think about a justice’s career that started with allegations of sexual harassment, moved on to extreme coziness with conservative political donors, then multiple instances of questionable gifts and payments to himself and his wife, and now revelations that years of free trips and perks lavished on him by right-wing billionaire Harlan Crow went unreported, despite laws that clearly say they should be? Even after the news of Crow’s largesse first broke, it got worse. Crow had also bought Justice Thomas’s mother’s house in Savannah, a helpful real estate deal that Justice Thomas never reported either.

We could think that Justice Thomas doesn’t know about the ethical standards expected of a Supreme Court justice or the laws that apply to him as a public employee. But he is a graduate of Yale Law School, ignorance is not a believable defence here.

That’s not the kind of person who belongs in the Supreme Court. If he wanted to do the decent and honourable thing, he would resign. Calls for him to resign are coming from pro-democracy groups, including the one I lead, top media outlets, and members of Congress.

But Thomas doesn’t have a history of doing the decent and honourable thing, so that means others will have to hold him accountable. The question is: How?

There are plenty of calls for impeachment, but with a Republican-controlled House that option would appear to be off the table. Meanwhile, the Senate will hold hearings and may call Justice Thomas himself to testify. That is an important step. I would add that two other steps are absolutely essential right now: a Department of Justice (DOJ) investigation and Supreme Court reform, including an enforceable code of ethics.

The DOJ has clear grounds to investigate Justice Thomas under a federal disclosure law that applies to government officials, including Supreme Court justices. The law authorises the DOJ to pursue both civil penalties and criminal fines from government officials who fail to report gifts as legally required.

Justice Thomas has claimed that the generosity he received from Crow was just “personal hospitality” – not subject to reporting. Even if some of that were true, some perks, like free use of Crow’s private jet for Thomas’s personal travel and the real estate transaction in Georgia, are, according to most ethics experts, clearly in a different category.

The DOJ can give a definitive answer as to whether Thomas’s actions were not only unsavoury, unethical, improper, and all the rest, but also absolutely illegal. And it can call for imposition of a monetary fine. Even more important than the cash fine would be the impetus a finding of guilt would give to any effort to remove Justice Thomas.

And then, to help ensure that trust in the court isn’t further eroded by scandal after scandal, we need to have Supreme Court reform. That means an enforceable code of ethics specifically for the court, written to address the full range of ethical questions that could ever apply to justices’ behaviour. In the longer term we should also have Supreme Court expansion to counteract the far-right capture of the court. But that is a larger conversation.

It has been painful to watch the impact Justice Thomas’s behaviour has had on the Supreme Court. This is especially true given the historic significance of the seat he occupies. We need judges in all our courts — not just the highest — who act with humility and who understand the impact of their decisions on everyday Americans. Courts really do make a difference in the lives of everyday people. They should be led by trustworthy, fair-minded judges who value equality and justice, uphold the constitution, and protect civil and human rights for all Americans.

That’s not Clarence Thomas.

Svante Myrick is president of People For the American Way. Previously, he served as executive director of People For and led campaigns focused on transforming public safety, racial equity, voting rights, and empowering young elected officials. Myrick garnered national attention as the youngest-ever mayor in New York State history.