Beginning with the 110th Congress, the PDF files of Public and Private Laws on GPO Access have been digitally signed and certified to assure users that the online documents are official and authentic. To search or browse Public and Private Laws go to GPO Access.
GPO Access is the website maintained by the U.S. Government Printing Office and provides free electronic access to various government documents. Click on this link for more information about how GPO has begun implementing digital signatures to certain electronic documents on GPO Access.