Last week we learned that some Republican members of Congress are considering articles of impeachment against Deputy Attorney General Rod Rosenstein if he doesn’t hand over certain Federal Bureau of Investigation documents. In January, House Speaker Paul Ryan had to threaten the deputy attorney general and FBI Director Christopher Wray with contempt to get them to comply with a House subpoena for documents about the Steele dossier.

I spent 33 years in the FBI, including several working in the Office of Congressional and Public...