There's been more news about the federally controlled mortgage giants Fannie Mae and Freddie Mac in recent days — and none of it is good news.

The cost of the federal bailout of the two companies, which buy mortgages from banks and other mortgage lenders and now own or guarantee the majority of home loans, is expected to grow to about $259 billion over the next few years.

Also last week, published reports said that Fannie and Freddie pressured a foreclosure processing law firm in Florida to speed up mountains of paperwork, which is now part of the emerging scandal involving so-called robo-signing of foreclosure documents.

Still, the bigger and more-troubling story is the role that Fannie Mae and Freddie Mac played in the financial crisis, and the cost to taxpayers for bailing out the two government-supported agencies.

While most taxpayers are aware of the TARP (Troubled Asset Relief Program) bailout program, not many people realize the costs of bailing out Fannie and Freddie. Another contrast is found in a recent report that most of the $700 billion in TARP money, used to prop up banks, insurance giant AIG (American International Group) as well as General Motors and Chrysler, has been, or will be, repaid. The latest estimates are that taxpayers will be on the hook for about $50 billion, or less, in unpaid TARP funds.

By contrast, the separate federal bailout of Fannie and Freddie keeps growing larger, with potential to get worse.

Last week's estimate of the cost of bailing out Fannie and Freddie says the two government-controlled agencies will likely be the largest bailouts of the financial crisis.

Given the massive costs, taxpayers should understand the central role that Fannie and Freddie played in helping to create the mortgage bubble and resulting financial crisis.

The agencies' historic mission of expanding home ownership was under increasing congressional pressure to accelerate and expand during the Clinton and George W. Bush administrations. While well-intentioned, the idea of helping more people buy their own homes was distorted by political pressure, and risks were overshadowed by real estate prices that seemed to only go up. Under pressure to expand home ownership in poor communities, the sub-prime market was born — and risks increased dramatically. Fueled by quick and easy profits in selling mortgages, banks and other loan originators lowered lending standards to the point that income records, credit scores, down payments and accurate information became an afterthought in many cases.

When questions were raised about the risky nature of many Fannie and Freddie mortgages, Congress resisted regulatory reform. U.S. Rep. Barnie Frank, D-Mass., famously said that Fannie and Freddie faced no financial troubles at all — and he favored "rolling the dice" further on risky sub-prime mortgages.

Efforts to reform the agencies or impose tougher loan stand-ards were politicized and those pushing to reduce risky loans were portrayed as anti-poor or racist. And beyond resistance to reform from many members of Congress, Fannie and Freddie lobbied to rebuff reform efforts, spending an estimated $155 million to prevent any curtailment of their increasingly risky operations.

Even two months before the federal seizure of Fannie and Freddie, Frank declared them both financially sound.

When the Financial Crisis Inquiry Commission (FCIC) issues its report in mid-December, the complete picture of Fannie and Freddie should be revealed. Though there were many factors that played a role in the financial crisis, the impact of Fannie Mae and Freddie Mac was central, as was the resistance to regulatory reform — from within the two companies and from key members of Congress.

The full story of how two government-backed companies helped pump up the inflated mortgage bubble must be known. Their bailouts dwarf the TARP bailout that has infuriated so many taxpayers. The story of Fannie and Freddie must be known so that those responsible are held accountable and so that it does not happen again.