Congressional Budget Office (CBO)
The Congressional Budget Office (CBO) is the primary congressional agency charged with reviewing congressional budgets and other legislative initiatives with budgetary implications. The CBO offers:
U.S. Government Accountability Office (GAO)
Known as "the investigative arm of Congress" and "the congressional watchdog," GAO supports the Congress in meeting its constitutional responsibilities and helps improve the performance and accountability of the federal government for the benefit of the American people.
Both the CBO and the GAO are excellent resources for public policy analysis and other initiatives.