His most successful effort was to impose what were called "affordable housing" requirements on Fannie Mae and Freddie Mac in 1992. Before that time, these two government sponsored enterprises (GSEs) had been required to buy only mortgages that institutional investors would buy--in other words, prime mortgages--but Frank and others thought these standards made it too difficult for low income borrowers to buy homes. The affordable housing law required Fannie and Freddie to meet government quotas when they bought loans from banks and other mortgage originators.
At first, this quota was 30%; that is, of all the loans they bought, 30% had to be made to people at or below the median income in their communities. HUD, however, was given authority to administer these quotas, and between 1992 and 2007, the quotas were raised from 30% to 50% under Clinton in 2000 and to 55% under Bush in 2007. Despite Frank's effort to make this seem like a partisan issue, it isn't. The Bush administration was just as guilty of this error as the Clinton administration. And Frank is right to say that he eventually saw his error and corrected it when he got the power to do so in 2007, but by then it was too late.
It is certainly possible to find prime mortgages among borrowers below the median income, but when half or more of the mortgages the GSEs bought had to be made to people below that income level, it was inevitable that underwriting standards had to decline. And they did. By 2000, Fannie was offering no-downpayment loans. By 2002, Fannie and Freddie had bought well over $1 trillion of subprime and other low quality loans. Fannie and Freddie were by far the largest part of this effort, but the FHA, Federal Home Loan Banks, Veterans Administration and other agencies--all under congressional and HUD pressure--followed suit. This continued through the 1990s and 2000s until the housing bubble--created by all this government-backed spending--collapsed in 2007. As a result, in 2008, before the mortgage meltdown that triggered the crisis, there were 27 million subprime and other low quality mortgages in the US financial system. That was half of all mortgages. Of these, over 70% (19.2 million) were on the books of government agencies like Fannie and Freddie, so there is no doubt that the government created the demand for these weak loans; less than 30% (7.8 million) were held or distributed by the banks, which profited from the opportunity created by the government. When these mortgages failed in unprecedented numbers in 2008, driving down housing prices throughout the U.S., they weakened all financial institutions and caused the financial crisis.
Congressman Frank makes assertions about who was responsible, but he, like all those who hold his position, have no data. He says that the banks were responsible, but cannot challenge the numbers I have outlined above. These numbers show, beyond question, that it was government housing policy that caused the financial crisis. Even he has admitted it. In an interview on Larry Kudlow's show in August 2010, he said "I hope by next year we'll have abolished Fannie and Freddie ... it was a great mistake to push lower-income people into housing they couldn't afford and couldn't really handle once they had it."