October 01, 2010, 6:37 PM EDT

By Kathleen M. Howley

Oct. 1 (Bloomberg) — U.S. courts are clogged with a record number of foreclosures. Next, they may be jammed with suits contesting property rights as procedural mistakes in those cases cloud titles establishing ownership.

“Defective documentation has created millions of blighted titles that will plague the nation for the next decade,” said Richard Kessler, an attorney in Sarasota, Florida, who conducted a study that found errors in about three-fourths of court filings related to home repossessions.

Attorneys general in at least six states are investigating borrowers’ claims that some of the nation’s largest home lenders and loan servicers are making misstatements in foreclosures. JPMorgan Chase & Co. is asking judges to postpone foreclosure rulings, while Ally Financial Inc. said Sept. 21 its GMAC Mortgage unit would halt evictions. The companies said employees may have completed affidavits without confirming their accuracy.

Such mistakes may allow former owners to challenge the repossession of homes long after the properties are resold, according to Kessler. Ownership questions may not arise until a home is under contract and the potential purchaser applies for title insurance or even decades later as one deed researcher catches errors overlooked by another. A so-called defective title means the person who paid for and moved into a house may not be the legal owner.