The nation faces a foreclosure crisis of historic proportions, and there is an understandable desire on the part of the federal government to "do something" to help. House Judiciary Chairman John Conyers's bill, which is moving swiftly through Congress (and companion legislation introduced by Sen. Richard Durbin) would allow bankruptcy judges to modify home mortgages by reducing both the interest rate and principal amount on the loan. This would be a profound mistake.

Mortgage modification would indeed provide a windfall for...