DENVER (AP) - A federal judge has halted the auction of an Aurora woman's home as he weighs whether Colorado's foreclosure law is constitutional.

U.S. District Judge William Martinez took the rare step Monday in the case of Lisa Kay Brumfiel. The part-time saleswoman is representing herself against U.S. Bank and one of Colorado's top foreclosure lawyers.

The law allows banks to assert their right to follow through on a foreclosure even if they don't have the paperwork to prove they hold the mortgage. The Denver Post reports that Martinez gave Brumfiel until May 15 to submit arguments about whether that violates the U.S. Constitution's equal protection clause.

Martinez said Colorado is the only state that allows lawyers to submit unsworn statements attesting that a particular bank has the right to foreclose.