You're referencing your own thread as a source? Seriously?
Actually, Carney makes a pretty compelling case. He also admits he changed his mind on the subject when presented with more evidence.
CRA had the effect of skewing the market by creating artificial demand. That's why prices on houses kept going up. If it had been limited to just people who could afford and pay mortgages, you wouldn't have had the kind of balooning we saw. But when you have the government essentially saying to banks, "You have to write bad loans, or we'll take you to court, but we are having Freddie and Fannie buy up 2 trillion in bad loans", you've pretty much invited disaster.
Not to say that there weren't a lot of other factors involved, too. Greedy, dishonest bankers being one of them. Lax government regulation under both Democrats and Republicans. (And still going on today. How many Banksters has Obama prosecuted?)
It's like any government program- subsidize bad behavior and then wonder why you get more of it.