SACRAMENTO, Calif. — Justice Elena Kagan on Thursday became the first member of the Supreme Court to call publicly for beefing up its new ethics code by adding a way to enforce it. In her first public remarks since the nation’s highest court wrapped up its term earlier this month, Kagan said she wouldn’t have signed onto the new rules if she didn’t believe they were good.

But having good rules is not enough, she said. “The thing that can be criticized is, you know, rules usually have enforcement mechanisms attached to them, and this one — this set of rules — does not,” Kagan said at an annual judicial conference held by the 9th Circuit. More than 150 judges, attorneys, court personnel and others attended.

It would be difficult to figure out who should enforce the ethics code, though it should probably be other judges, the liberal justice said, adding that another difficult question is what should happen if the rules are broken. Kagan proposed that Chief Justice John Roberts could appoint a committee of respected judges to enforce the rules. Democrats, including President Joe Biden, have renewed talk of Supreme Court reforms , including possible term limits and an ethics code enforceable by law.

The court had been considering adopting an ethics code for several years, but the effort took on added urgency after ProPublica reported last year that Justice Clarence Thomas did not disclose luxury trips he accepted from a major Republican donor. ProPublica also repor.