The most reliable and persuasive evidence of legislative intent is generally believed to be in the texts of Congressional reports. Reports describe the purpose and intent of a bill and offer rationales for its approval.

Reports are submitted to the Congress by the Congressional committees which have studied the proposed legislation. When differing versions of legislation are passed by the House and Senate, a conference committee usually resolves the differences and issues its own report. Reports may also be written for reasons not related to specific proposed legislation, such as to summarize committee oversight or investigative functions.

House and Senate reports are individually numbered. The number indicates the Congress but does not have any relationship to the bill number under consideration.

Reports are identified in the CIS Annual from 1970 to date. Prior to 1970 they are indexed in the CIS U.S. Serial Set Index, 1789-1969. Indexing terms include the bill number under consideration, the subject of the legislation, the report number, and the Superintendent of Documents (SuDocs) classification number. Other indexes that identify House, Senate, and conference committee reports are the Catalog of U.S. Government Publications, the Numerical Lists and Schedule of Volumes of the United States Congressional Serial Set from 1933-1980, the Monthly Catalog U.S. Congressional Serial Set Supplement for the 97th Congress, and the United States Congressional Serial Set Catalog since the 98th Congress in 1983.

The texts of selected reports are reprinted in the United States Code Congressional and Administrative News (U.S.C.C.A.N.). Since the 99th Congress, U.S.C.C.A.N. has reprinted the texts of both the House and Senate reports; prior to the mid-1980's U.S.C.C.A.N. reprinted usually only the more significant report. U.S.C.C.A.N. is arranged by public law number and has a subject index that indicates the page on which the legislative history report begins.

The lh database on Westlaw contains reports identical to U.S.C.C.A.N. until 1990 after which all committee reports are available online. The cmtrpt file in the legis and codes libraries on LexisNexis contains current reports since 1990. Both Westlaw and LexisNexis have legislative history databases in a few selected subjects, such as tax and bankruptcy, which contain the texts of committee reports. Lexis Advance has reports since 2000 and Bloomberg Law has reports since 1995. Selected reports are available on HeinOnline in the U.S. Federal Legislative History Library.

FDsys and provide committee reports from 1995 (104th Congress) to the present. 

From 1970 to 1980 & 1993 to date, committee reports at Cardozo are found on CIS microfiche under the CIS abstract number. From 1980 to date, reports are filed in the Superintendent of Documents (SuDocs) collection. These fiche are filed by the  SuDocs classification number; House reports begin Y 1.1/8:. Senate reports begin Y 1.1/5:. The SuDocs number is given in the various CIS indexes. 

Reports are also available in the bound United States Congressional Serial Set from 1977 to date. From 1889-1896 and 1909-1969, the Serial Set is available on CIS microfiche. From 1979 to date the Serial Set can be found in the Superintendent of Documents collection (SuDocs) of microfiche under the numbers X: (96th Congress only) and Y 1.1/2: [serial set volume number]; only title pages and contents are filed under this number. The numbering of the Serial Set is in a numerical sequence which differs from the actual report number. The Serial Set volume number is found in the Numerical Lists, Serial Set Catalog, and CIS U.S. Serial Set Index. ProQuest Congressional contains digitized reports and documents from 1817-1971 and is available through BEN. 

The American State Papers compile the most important reports from the first 14 Congresses (1833-1817) and additional selective reports until 1838. Each volume has its own index. The series is also indexed in the CIS U.S. Serial Set Index. HeinOnline also has the digital version of the American State Papers.