Bloomberg Law is a database known for its analysis of corporate news and financial markets, however it is also making its mark as a legal database -- offering federal and state cases, legislation, briefs, dockets and numerous secondary resources. Currently, some of the documents are in pdf format but most of the database documents are in xml format.
For a detailed overview of the federal legislative history process, refer to the UW Law Library LibGuide on this topic, atuhored by Bonnie Shucha.