Mark S. Zaid, the activist attorney representing the so-called whistleblower at the center of the impeachment movement targeting President Donald Trump, advocated for Robert S. Mueller III to become an anti-Trump whistleblower. On April 25, 2018, while Mueller’s Office of the Special Counsel was investigating ultimately collapsed claims of collusion between Russia and Trump’s presidential campaign, Zaid co-authored an oped in the New York Times calling for Mueller and his staff to become “lawful whistle-blowers.” The scheme outlined by Zaid was an option to be implemented if Trump had moved to fire Mueller and dismantle the Special Counsel’s office. Zaid...