A guy with a checkered past is a guy with a checkered past except in goofy movies and goofier conspiracy theories.
The term “conspiracy theory” was invented by the men involved in the murder of a particular well known individual approximately 54 years, 11 months and 5 days ago.
They invented it as a psychological method for discouraging anyone from considering that perhaps there was more than a single shooter in that incident, and probably also to discourage people from suspecting their agency of anything nefarious, ever.
In other words, the term “conspiracy theory” is meaningless other than for brainwashing.