Could a "Bear Raid" have caused the '08 market crash?

The possibility that something like this happened is pretty obvious to anyone who understands how the sausage is made on Wall Street. Yes, people can and do conspire behind the scenes whether it's illegal or not. Yes, insider trading occurs. Yes, certain actors have many orders of magnitude more money under their control than others. And yes there is now a much higher volume of computerized trading than in decades past, with more complexity, more abstraction, and more layers of indirection. It's like running a shell game against a mark, except you're now able to maintain thousands of shells under which to hide the nut as you move it around. And move them at extremely high speeds. If you plan a con or scam or "raid" but construct it well enough to cover your trail, have plausible deniability, and/or not do anything which is strictly illegal (and if you have millions or especially billions of dollars at your disposal, you almost certainly can afford to have many great lawyers helping you to ensure that this is the case), then it seems reasonable to assume that one can get away with the white-collar equivalent of a bank robbery.

The headline is overly sensational. The volume of the transactions mentioned there sounds enough to manipulate one stock, but not enough to cause a complete crash. This is particularly clear when you compare it to the sheer volume of subprime loans created by control fraud and predatory lending that were starting to collapse in 2008. There are orders of magnitudes in difference.

That said, the real story behind the hype does sound plausible, and stuff like that just highlights how absurd the notion of "efficient free markets" really is. You need transparency, you need regulation, and most importantly you need prosecution.