In a new op-ed, Fox News senior judicial analyst Andrew Napolitano debunked President Donald Trump’s “hoax” defense in his Senate impeachment trial and argued that there was “ample” evidence to remove the president from office.

“It is deadly serious business based on well-established constitutional norms,” the former New Jersey Superior Court judge wrote of the trial in a column published on the conservative news network’s website Thursday.

Napolitano broke down the events that led to Trump being put on trial in the GOP-controlled Senate over his Ukraine misconduct. Trump has denied wrongdoing and called his impeachment “a hoax.”

It “leaves us with valid, lawful, constitutional arguments for Trump’s impeachment that he ought to take seriously,” wrote Napolitano, who has not shied away from criticizing Trump and his administration in recent months.

“What is required for removal of the president?” Napolitano asked. “A demonstration of presidential commission of high crimes and misdemeanors, of which in Trump’s case the evidence is ample and uncontradicted.”