An operative who uses his platform to influence the perception of a person, organization, or event. Like a damage-control
PR person.
Most often this is in the political context, usually conservative, with the spin doctor
masquerading as a journalist or "expert in the field" to lend credibility to what's actually just a PR line
cooked up by the right-wing.
After "Deep Throat" finally revealed himself as W.
Mark Felt in May, 2005, a parade of
spin doctors, old Nixon cronies and convicted Watergate felons appeared in the media, trying to tarnish Felt in any way they could, to distract from and lessen in the public's mind the
enormity of the crimes they'd committed 30 years ago.