Abuses of government power are generally boring facts, like civil asset forfeiture. “A conspiracy theory is an explanation for an event or situation that asserts the existence of a conspiracy by powerful and sinister groups, often political in motivation, when other explanations are more probable.” https://en.wikipedia.org/wiki/Conspiracy_theory

So, when cops rob an armored car via civil asset forfeiture it’s just something that happened no conspiracy theory required because there isn’t some other example that fits. But, the moon landing was fake fits because there’s another explanation.

Occasionally what once was a conspiracy theory is now considered factual, but at that moment it stops being a conspiracy theory because it’s no longer fringe. As such this isn’t a pejorative definition as it doesn’t directly imply such theories are incorrect.