WATCH: Law professor addresses unprecedented nature of judicial attacks under Trump administration

Kate Shaw, a law professor at the University of Pennsylvania law school, said Tuesday that the attacks she’s seen from government officials on the judiciary are unprecedented and she worries they’ll lead to unchecked presidential power.

Watch the video in our player above.

Shaw was responding to questions from Sen. Adam Schiff, D-Calif., who asked her about whether she’s seen historical precedents for attacks by President Donald Trump on judges whose rulings he disagrees with. She said that while tension between judges and the people who appoint them is not new, current attacks, including impeachment threats and identifying members of judges’ families, are.

“I do think that those threats represent sort of a new escalation that is deeply concerning,” Shaw said.

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Schiff also asked her to put the attacks in a broader context, saying he considered them “part of a concerted effort to attack the rule of law,” with which Shaw agreed.

Sen. Josh Hawley, R-Mo., also questioned Shaw on Tuesday over her stance on federal judges issuing nationwide injunctions. Hawley repeatedly asked Shaw to provide a principle under which she thinks it’s reasonable for judges to issue nationwide injunctions. Watch in the video below.

“I think if the Constitution is committed to a single principle, it is limits on power,” Shaw said. “I worry that we are on a path toward few, if any, meaningful limits on the president.”

Shaw was testifying before a Senate Judiciary subcommittee hearing on the federal judiciary, with Republican senators particularly focused on the use of nationwide injunctions to stymie Trump’s agenda.