Congressional Rules Pertaining to Changes in Mandatory Program Spending in Appropriations Bills (CHIMPs)

When Congress considers legislation, it takes into account the proposal’s potential budgetary effects. This helps Members to weigh the legislation’s merits and to consider whether it complies with the budgetary rules that Congress has created for itself. One of these rules concerns the way in which the budgetary effects of certain changes in spending associated with mandatory spending programs—programs for which spending is typically controlled through laws other than appropriations acts—will be treated for budget control purposes. In particular, when changes to mandatory spending are included in appropriations measures, they are colloquially referred to as CHIMPs, or changes in mandatory programs, and their budgetary effects are attributed to the Appropriations Committee rather than the legislative committee that would otherwise have jurisdiction over that program. In many cases, this allows them to be used as an offset for discretionary spending. As such they are important for understanding how scorekeeping works in the context of congressional budget process rules. To understand what CHIMPs are and why they exist, it is first necessary to discuss how Congress assesses the budgetary effect of legislation. While information on the potential budgetary effects of legislation may come from numerous sources, the authority to determine whether legislation complies with congressional budgetary rules is given to the House and Senate Budget Committees. In this capacity, the Budget Committees generally rely on estimates (or “scores”) that are statutorily required to be provided by the Congressional Budget Office (CBO) and the Joint Committee on Taxation (JCT). When producing cost estimates, CBO and JCT are directed to adhere to scorekeeping guidelines—specific rules for determining or attributing certain budgetary effects of legislation—that were first agreed to in conjunction with the Budget Enforcement Act of 1990. These general guidelines are meant to ensure consistent enforcement of various procedural and statutory budgetary requirements. One of these guidelines requires that, when increases or decreases in mandatory spending are included in an appropriations measure, they are attributed to the Appropriations Committee. As a consequence, the net budgetary impact of such changes (CHIMPs) will be added to or subtracted from discretionary spending in the bill to determine compliance with any procedural and statutory limits imposed on discretionary spending. In many cases, the projected budgetary effect of a CHIMP is a net savings, but CHIMPs may be projected to have a net cost or no impact on the budget. If the budgetary effect of a CHIMP is to reduce or otherwise restrict the projected level of spending for a mandatory program, thus producing net savings, it could be used to offset an increase in the amount of discretionary spending that could be provided elsewhere in the appropriations bill. While congressional scorekeeping rules explicitly allow for CHIMPS, and the practice is not uncommon, Members of Congress have sometimes criticized their use for various reasons. In response to such concerns, in recent years Congress has periodically adopted rules that would restrict the inclusion of CHIMPs in appropriations legislation. The only formal restriction on CHIMPS currently, however, is a Senate prohibition against certain CHIMPS with net costs.