J.P. Morgan is freezing about 56,000 foreclosures in 23 states as it deals with allegedly forged documents and signatures being used to undo evictions. The bank, one of the nation’s biggest, could inspire others to follow suit, as Fitch Ratings officials say the faulty paperwork is a problem across the industry. In response, the ratings agency says it might downgrade many lenders’ mortgage servicing divisions. The J.P. Morgan announcement follows a similar move at Ally Financial, formerly GMAC; both companies are investigating whether their employees improperly compiled foreclosure files and then failed to make sure they were justified before giving the paperwork their seal of approval. One of J.P. Morgan’s employees said in a sworn statement that her team approved 18,000 foreclosures without checking them. If lenders follow J.P. Morgan’s lead, foreclosures would slow across the country.