NEW YORK -- The nation's five largest mortgage firms have saved more than $20 billion since the housing crisis began in 2007 by taking shortcuts in processing troubled borrowers' home loans, according to a confidential presentation prepared for state attorneys general by the nascent consumer bureau inside the Treasury Department.

That estimate suggests large banks have reaped tremendous benefits from under-serving distressed homeowners, a complaint frequent enough among borrowers that federal regulators have begun to acknowledge the industry's fundamental shortcomings.

The dollar figure also provides a basis for regulators' internal discussions regarding how best to penalize Bank of America, JPMorgan Chase, Wells Fargo, Citigroup and Ally Financial in a settlement of wide-ranging allegations of wrongful and occasionally illegal foreclosures. People involved in the talks say some regulators want to levy a $5 billion penalty on the five firms, while others seek as much as $30 billion, with most of the money going toward reducing troubled homeowners' mortgage payments and lowering loan balances for underwater borrowers, those who owe more on their home than it's worth.

Even the highest of those figures, however, pales in comparison to the likely cost of reducing mortgage principal for the three million homeowners some federal agencies hope to reach. Lowering loan balances for that many underwater borrowers who owe less than $1.15 for every dollar their home is worth would cost as much as $135 billion, according to the internal presentation, dated Feb. 14, obtained by The Huffington Post.

But perhaps most important to some lawmakers in Washington, the mere existence of the report suggests a much deeper link between the Bureau of Consumer Financial Protection, led by Harvard professor Elizabeth Warren, and the 50 state attorneys general who are leading the nationwide probe into the five firms' improper foreclosure practices, a development sure to anger Republicans in Congress and a banking industry intent on diminishing the fledgling CFPB's legitimacy by questioning its authority to act before it's officially launched in July.

Earlier this month, Warren told the House Financial Services Committee, under intense questioning, that her agency has provided limited assistance to the various state and federal agencies involved in the industry probes. At one point, she was asked whether she made any recommendations regarding proposed penalties. She replied that her agency has only provided "advice."

A representative of the consumer agency declined to comment on the presentation, citing the law enforcement nature of the federal investigation into the mortgage industry's leading firms.

The seven-page presentation begins by stating that a deal to settle claims of improper foreclosures "provides the potential for broad reform."

In it, the consumer agency outlines possibilities offered by the settlement -- a minimum number of mortgage modifications, a boost to the housing market -- and how it could reform the industry going forward so that investors in home loans and the borrowers who owe them would be able to resolve situations in which borrowers fall behind on their payments without the complications of a large mortgage company acting in its own interest.

The presentation also details how much certain firms likely saved in lieu of making the necessary loan-processing adjustments as delinquencies and foreclosures rose. Bank of America, for example, has saved more than $6 billion since 2007 by not upgrading its procedures or hiring more workers, according to the report. Wells Fargo saved about as much, with JPMorgan close behind. Citigroup and Ally bring the total saved to nearly $25 billion.

The presentation adds that the under-investment far exceeds the proposed $5 billion penalty that has been on the table. People familiar with the matter say the Office of the Comptroller of the Currency wants to fine the industry less than $5 billion.

The alleged shortchanging of homeowners has prolonged the housing market's woes, experts say, because distressed homeowners who are prime candidates to have their payments reduced aren't getting loan modifications and lenders are taking up to two years to seize borrowers' homes.

The average borrower in foreclosure has been delinquent for 537 days before actually being evicted, up from 319 days in January 2009, according to Lender Processing Services, a data provider.

The prolonged housing pain has manifested itself in various ways.

Purchases of new U.S. homes dropped last month to the slowest pace on record, according to the Commerce Department. Prices declined to the lowest level since 2003, according to the National Association of Realtors. About 6.9 million homeowners were either delinquent or in foreclosure proceedings through February, according to LPS.

A penalty of about $25 billion -- based on mortgage servicing costs avoided -- would have "little effect" on the five firms' capital levels, according to the presentation, since the five banks collectively hold about $500 billion in tangible common equity, the highest form of capital. Those numbers notwithstanding, banks and Republicans in Congress have complained that such a large penalty would have a disproportionate impact on bank balance sheets, hurting their ability to lend or pay dividends to investors.

The presentation adds that given the extent of negative equity -- underwater homeowners owe $751 billion more than their homes are worth, according to data provider CoreLogic -- "we have gravitated towards settlement solutions that enable asset liquidity and cast a wide net." The solution is an emphasis on reducing mortgage debt and enabling short sales, thus allowing borrowers to refinance into more affordable loans or to sell their homes and move on.

Top Federal Reserve officials and other economists have pointed to the large numbers of underwater homeowners as being one of the reasons behind high unemployment, as underwater homeowners are unable to move to where the jobs are. More than 23 percent of homeowners with a mortgage are underwater, according to CoreLogic.

The proposed settlement, as envisioned by the consumer agency, could reduce loan balances for up to three million homeowners. If mortgage firms targeted their efforts at reducing mortgage debt for three million homeowners who owe as much as their homes are worth or have less than 5 percent equity, the total cost would be $41.8 billion, according to estimates cited in the presentation.

If firms lowered total mortgage debt for three million homeowners who are underwater by as much as 15 percent and brought them to 5 percent equity, that would cost more than $135 billion, according to the presentation. That would include reducing second mortgages and home equity lines of credit.

In its presentation, the consumer agency said the new program, titled "Principal Reduction Mandate," could be "meaningfully additive to HAMP" -- the Home Affordable Modification Program, the Obama administration's primary mortgage modification effort.

The CFPB estimates that there are about 12 million U.S. homeowners underwater, most of whom are not delinquent, according to its presentation. Of those, nine million would be eligible for this new principal-reduction scheme born from the foreclosure deal. The new initiative would then "mandate" three million permanent modifications.

News of the level of the consumer agency's involvement in the state investigation would likely be welcomed by consumer and homeowner advocates, who have long complained of the lack of attention paid to distressed borrowers by federal bank regulators like the OCC and the Federal Reserve.

But Republicans will pounce on the news, creating yet another distraction for a fledgling bureau that was the centerpiece of the Obama administration's efforts to reform the financial industry in the wake of the worst economic crisis since the Great Depression.

Meanwhile, the banking industry will likely celebrate government infighting as attention is diverted away from allegations of bank wrongdoing and towards the level of involvement of Elizabeth Warren, a fierce consumer advocate and the principal original proponent of an agency solely dedicated to protecting borrowers from abusive lenders.

Warren is standing up the agency on an interim basis. It formally launches in July, at which point it will need a Senate-confirmed director in order to carry out its full authority. One of those areas will be how mortgage firms process home loans for distressed borrowers.

A spokeswoman for JPMorgan Chase declined to comment. Spokespeople for the other four banks were not immediately available for comment.

Read the presentation below:

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