Mortgage lenders are eager to tap into what they see as a $44 billion marketplace – housing loans for illegal aliens.

Banks across the United States are writing loans based on individual taxpayer identification number, or ITIN. They are easy to get, even if you are ineligible for a Social Security card.

The Internal Revenue Service issues them and expects recipients to file tax returns. The IRS doesn't report illegal aliens to immigration officials.

Mortgage lenders don't care if applicants are legal or illegal. They simply make a business decision in approving or disapproving a loan.

Not everyone approves of the program, however.

"It is a threat to national security and public safety and is morally bankrupt," Dan Stein, president of the Federation for American Immigration Reform, a Washington-based group that favors tighter immigration controls, told Newhouse News. "It breeds ultimate contempt for laws."

Banks "ought to be part of the solution in ensuring that people who apply for mortgages and conduct other business are here legally," Stein said. "They went down the road of making a fast buck in a way that is frankly, in our view, inconsistent with the spirit of patriotism and federal law."

In addition to accepting ITINs, banks are being flexible when they look at credit reports, since many immigrants don't have a traditional credit history. For instance, say lending sources, the bank may consider rent and utility bill payments, or a history of sending money to family overseas as evidence that a customer is a good risk.

One company, Milwaukee-based Mortgage Guaranty Insurance, now offers private insurance on the loans, which reduces risks for banks and makes the mortgages easier to resell. The Federal Deposit Insurance Corp. is helping a group of Midwest banks to develop ITIN programs.

Freddie Mac, the Federal Home Loan Mortgage, is studying whether to buy the mortgages from banks.

Without the participation of a major institution like Freddie Mac or Fannie Mae, the Federal National Mortgage Association – which together holds 37 percent of U.S. residential mortgage debt – the spread of ITIN mortgages will be limited. Now, most banks making the loans must hold onto them, rather than selling them for cash that could be used for additional mortgages.