Helping a patron research the concept of “positive law” prompted me to post here a pair of links to documents discussing the Positive Law Codification project being conducted by the Office of the Law Revision Counsel and a brief but very informative review of US Code concepts.  I found both of these among the excellent collection of Federal legislative research materials posted on the web site of the Law Librarians’ Society of Washington, D.C. (LLSDC).  Many thanks to Richard McKinney, the staff at the Office of the Law Revision Council and the LLSDC.