Does Congress know enough to legislate for the nation? Reforms over the last two decades, increasing the number of congressional staff and enhancing congressional support agencies, have dramatically expanded the availability of policy information. In a groundbreaking new study of congressional communication networks, David Whiteman finds that, although on any particular issue there are very few in Congress undertaking extensive searches for information, the collective base of information generated by all searches is unexpectedly comprehensive.

As Whiteman reminds us, communication lies at...