An editorial from the Washington Post:

“Mistakes were made,” the agency said in a statement. IRS official Lois Lerner explained that staffers used a “shortcut” to sort through a large number of applications from groups seeking tax-exempt status, highlighting organizations with “tea party” or “patriot” in their names. The IRS insisted emphatically that partisanship had nothing to do with it. However, it seems that groups with “progressive” in their titles did not receive the same scrutiny.