We investigate the networks of committee and subcommittee assignments in the United States House of Representatives from the 101st--108th Congresses, with committees connected according to ``interlocks'' or common membership. We examine the House's community structure using several methods, which reveal strong links between different committees as well as the intrinsic hierarchical structure within the House as a whole. We identify structural changes, including additional hierarchical levels and higher modularity, resulting from the 1994 elections, in which the Republican party earned majority status in the House for the first time in more than forty years. We also combine our network approach with analysis of roll call votes using singular value decomposition to uncover correlations between the political and organizational structure of House committees
