The GSEs participated in the expansion of subprime and other risky mortgages, but they followed rather than led Wall Street and other lenders into subprime lending. Writing in January 2011, three of the four Republicans on the FCIC Commission though dissenting from other conclusions of the majority, found that U.S. housing policy was, at the most, only one of the causes of the crisis. The three wrote: "Credit spreads declined not just for housing, but also for other asset classes like commercial real estate. This tells us to look to the credit bubble as an essential cause of the U.S. housing bubble. It also tells us that problems with U.S. housing policy or markets do not by themselves explain the U.S. housing bubble." In his lone dissent to the majority and minority opinions of the FCIC, Commissioner Peter J. Wallison of the American Enterprise Institute (AEI) blamed U.S. housing policy, including the actions of Fannie & Freddie, primarily for the crisis, writing: "When the bubble began to deflate in mid-2007, the low quality and high risk loans engendered by government policies failed in unprecedented numbers. The effect of these defaults was exacerbated by the fact that few if any investors—including housing market analysts—understood at the time that Fannie Mae and Freddie Mac had been acquiring large numbers of subprime and other high risk loans in order to meet HUD’s affordable housing goals." His dissent relied heavily on the research of fellow AEI member Edward Pinto, the former Chief Credit Officer of Fannie Mae. Pinto estimated that by early 2008 there were 27 million higher-risk, "non-traditional" mortgages (defined as subprime and Alt-A) outstanding valued at $4.6 trillion. Of these, Fannie & Freddie held or guaranteed 12 million mortgages valued at $1.8 trillion. Government entities held or guaranteed 19.2 million or $2.7 trillion of such mortgages total. As of January 2008, the total value of U.S. mortgage debt outstanding was $10.7 trillion. Wallsion publicized his dissent and responded to critics in a number of articles and op-ed pieces, and New York Times Columnist Joe Nocera accuses him of "almost single-handedly" creating "the myth that Fannie Mae and Freddie Mac caused the financial crisis". Critics contend that Fannie Mae and Freddie Mac affected lending standards in many ways - ways that often had nothing to do with their direct loan purchases:  In 1995 Fannie and Freddie introduced automated underwriting systems, designed to speed-up the underwriting process.