Six of the biggest banks in the nation have been told by New Jersey's Supreme Court Chief Justice that unless they can prove otherwise, they will have to stop tens of thousands of foreclosures in the Garden State.

"This is something we have focused on for a number of months," Chief Justice Stuart Rabner told NBCNewYork in a conference call with reporters Monday afternooon.

New Jersey's action follows similar moves in other states where lawyers for homeowners have found bankers using so-called "robo signing" to process the paperwork of foreclosures, when court rules require the banker involved to have specific knowledge of each case.

The banks involved include Bank of America, Ally (formerly GMAC), JP Morgan Chase, One WestBank (formerly Indybank), Citibank, and Wells Fargo.

Together, they filed 29,000 foreclosure notices so far this year, nearly half of the 65,000 to date.

In addition, the Court is demanding that two dozen smaller lenders prove that they are on the up and up with all of their foreclosure actiions, and must provide proof to a Special Master that they did not use any shortcuts in moving people out of their homes.

In New Jersey, a lender can begin foreclosure action only after four months of a homeowner being in arrears.

But the process of getting people out of their homes has to go through the courts, and while it is usually up to a Judge to decide, he or she normally relies on affadavits by banking officials that in New Jersey, require some detailed personal knowledge.

Legal Services of New Jersey, apparently following up on reports of sloppy foreclosures elsewhere, began a multi month investigation that formed the basis of today's action by Chief Justice Rabner.

In all, three fourths of the 65 thousand foreclosure filings made so far this year are being questioned by this action, with the six big banks being told to appear in a Mercer County courtroom January 19th to prove they're not guilty as charged.

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