Businessman William D. Campbell was honestly working on the Uranium One deal (though designed to benefit the Clinton Foundation) when he saw monkey-business and reported it to the FBI (when Robert Mueller was its director) whereupon Campbell became a confidential informant, but Stephan Halper was not working within the Trump campaign when he was tapped by the FBI to try to worm into the campaign looking for malfeasance, big difference, which is why Mr. Campbell is called a confidential informant while Halper is called a spy.
