Only half of the US Code is authoritative (so called 'positive law titles'). For the rest, the original statutes are authoritative. For the authoritative part-

Only half of the US Code is authoritative (so called 'positive law titles'). For the rest, the original statutes are authoritative. For the authoritative part- Congress isn't the only stakeholder who wants to see the law published correctly, fortunately. Businesses, lawyers, federal agencies, and others are looking over the US Code as it is published. In many ways it's like the open source model: many eyes and many copies (e.g. in libraries) keep it safe. The law is 200+ years old, though, so we're still stuck with old-timey ways of doing it for now. Congress is very quickly modernizing now. They recently converted the US Code into very good XML: http://uscode.house.gov/download/download.shtml http://uscode.house.gov/download/download.shtml. Anyone could copy it into github or run it through diff to see changes.