Define criminals/gangs, etc.

I think that's going to be crucial for your argument. What do you consider criminals/gangs? A lot of political parties would fit very well within a lot of definitions for that, but if you're thinking more Bloods and Crips then perhaps not.

But the factions involved in fifth century Athens and the use of ostracism to make the people feel like they were deciding when it was just "gangs" controlling the demos for their own benefit certainly disrupted power and put influential groups into seats of power (i.e. Themistocles, Pericles). And then there's other issues like just influencing the population through accusations, witch-hunting, and turmoil (e.g. the profanation of the Eleusinian Mysteries, the destruction of the Herms), which allowed for political arrests and trials with the public support.