I honestly don't know, but I would imagine someone would have to say the wrong thing to the wrong person or an investor with political clout gets burned and complains.
The SEC has a market abuse unit, maybe ask them to review if you think that's what's really going on. I'll be the first to admit that I don't know enough to even have an opinion if that's occurring. http://www.sec.gov/complaint/select.shtml
News 
Market Data 
Discover 
