Chief Justice John Roberts warned a group of graduating laws students Monday that the rule of law is “endangered.” Without naming any names, the conservative justice also said during an event with students at Georgetown University that recent attacks against Supreme Court justices have gone too far.

The US Supreme Court on Thursday heard arguments over whether individual federal judges can block Donald Trump’s executive orders across the country. It is the first time the court has weighed in on whether judges in lower courts can block the president’s policies nationwide and could have wide-ranging implications for Trump’s ability to implement his second-term agenda.