Citing government documents can be tricky because they aren't like any other kind of information you cite for a paper. Each kind of document -- court proceeding, congressional bill, supreme court decision -- requires different treatment according to the style you are working with. That doesn't mean you should be swayed from using this rich source of information! According to its strategic plan, the Government Publishing Office seeks to "keep American informed" and you are a part that.
When citing government documents, you follow the style guide you are currently using....but with the caveats of citing government documents. Don't worry, there are guides to help you get it right.