Democratic megadonor Tom Steyer on Sunday seemed unsure what crimes, legally worthy of impeachment, President Donald Trump has committed.

“The Constitution sets the ground for impeachment as treason, bribery, or other high crimes and misdemeanors,” CNN’s Dana Bash asked Steyer. “Which has the president violated?”

“I would say it’s clear that he has violated the Constitution in the sense that he has violated his trust with the American people through obstructing justice by firing the head of the FBI, Mr. Comey, for what he said explicitly was over the Russia investigation,” Steyer said.

The California-based billionaire also claimed Trump has been taking payments from foreign governments “in contradiction of the Emoluments Clause.”