Why Look at Congressional Committee Prints?

A congressional committee may request a special study in a specific subject area relating to proposed legislation; these are called committee prints. Committee prints often provide valuable information such as statistical analyses or historical background research.
Here’s more info from the Government Printing Office:
“Congressional committee prints are publications issued by congressional committees on topics related to their legislative or research activities. They are an excellent resource for statistical and historical information, and for legislative analysis. The subjects of the committee prints vary greatly, due to the different concerns and actions of each individual committee. Some basic varieties of committee prints include: draft reports and bills, directories, statistical materials, investigative reports, historical reports, situational studies, confidential staff reports, hearings, and legislative analyses.
The prints are generally viewed as internal background information publications and often are not announced for public distribution. Procedures for the printing and publication of these prints differ with each committee, and formats are inconsistent. Few prints have been allocated serial numbers, but most have not. The individual committee prints are not a part of the U.S. Congressional Serial Set, because those documents come from the Senate and the House of Representatives as a whole.
Committee prints do not have a consistent numbering system or publication history, the reason being that these papers are printed copies of committee members’ work. The Senate has a numbering system for its committee prints, but the House does not (e.g. “S. Prt. 108-3”).
GPO Access contains congressional committee prints for the 105th Congress (1997-98) forward. Documents are available in ASCII text and, in some cases, in Adobe Portable Document Format (PDF).”