"American federalism, which shapes the roles, responsibilities, and interactions among and between the federal government, the states, and local governments, is continuously evolving, adapting to changes in American society and American political institutions," according to the report. "The nature of federalism relationships in surface transportation policy has evolved over time, with the federal government's role becoming increasingly influential, especially since the Federal-Aid Highway Act of 1956, which authorized the Interstate Highway System."

The report traces the federal role in transportation policy back to the nation's establishment under the Constitution in 1789. Relatively recent congressional attention to federalism issues in this area, as the report points out, tends to increase during reauthorizations of the federal highway and transit program.

With the current extension of that program now set to expire March 4, the report weighs the historical context of federalism in light of various priorities that will likely be taken up during the 112th Congress -- including possible transference of programmatic responsibilities to the states and proposed changes to requirements at the state level for both maintenance of effort and cost-matching.

One major aspect of setting federal policy involves how those congressional committees responsible for transportation are set up and compartmentalized, the report states.

In the House, for example, programmatic and funding distribution matters fall under the jurisdiction of the Transportation and Infrastructure Committee while tax and Highway Trust Fund issues end up with the Ways and Means Committee. On the Senate side, most of the programmatic and funding distribution issues for highways are handled by the Environment and Public Works Committee while transit concerns fall under the Banking, Housing, and Urban Affairs Committee. Highway Trust Fund issues in the Senate go to the Finance Committee. Highway safety and railroad issues, meanwhile, are dealt with by the Commerce, Science, and Transportation Committee.

This situation of having numerous committees involved in transportation policy and funding has arguably "made it more difficult for Congress to develop broad-based policies that cut across committee jurisdictions or to enact proposals to consolidate programs or devolve programmatic authority to states as those actions might upset existing power relationships and require the consent of several committees and committee chairs," according to the report.

When it comes to external forces that influence congressional actions on surface transportation, the report highlights the significant role historically played by various public and private groups. While those groups are generally united in advocating for increased federal funding, there remain key differences on how the money should be allocated among states as well as transportation modes. A big challenge for Congress, according to the report, entails how to address and balance those differences while still promoting the national interest.

Another influential force, albeit one tougher to account for, encompasses American society's changing nature and expectations over time when it comes to personal mobility. As the nation has steadily moved from its primarily agrarian roots to assume a more urban and suburban character, the demand for greater personal mobility -- exemplified through such means as automobile ownership -- has only increased, the report notes. Congress has sought to address that public need by providing the states with programmatic flexibility but also retaining a federal presence through national oversight and guidelines.

It remains to be seen how all of these factors and others will unfold and align during the current congressional session.

"One certainty is that Congress will play the key role in determining the future of federalism relationships in surface transportation policy," the report concludes.

The 39-page report, "Federalism Issues in Surface Transportation Policy: Past and Present," is available at bit.ly/CRSfederalism.