A generation ago, it was common and uncontroversial for federal judges to rely upon legislative history when interpreting a statute. But since the 1980s, the textualist movement, led by Justice Scalia, has urged the banishment of legislative history from the judicial system. The resulting debate between textualists and their opponents — a debate that has dominated statutory interpretation for a generation — cannot be truly understood unless we know how legislative history came to be such a common tool of interpretation to begin with. This question is not answered by the scholarly literature, which focuses on how reliance on legislative history became permissible as a matter of doctrine (in the Holy Trinity Church case in 1892), not on how it became normal, routine, and expected as a matter of judicial and lawyerly practice. The question of normalization is key, for legislative history has long been considered more difficult and costly to research than other interpretive sources. What kind of judge or lawyer would routinize the use of a source often considered intractable?
Drawing upon new citation data and archival research, this Article reveals that judicial use of legislative history became routine quite suddenly, in about 1940. The key player in pushing legislative history on the judiciary was the newly expanded New Deal administrative state. By reason of its unprecedented manpower and its intimacy with Congress (which often meant congressmen depended on agency personnel to help draft bills and write legislative history), the administrative state was the first institution in American history capable of systematically researching and briefing legislative discourse and rendering it tractable and legible to judges on a wholesale basis. By embracing legislative history circa 1940, judges were taking up a source of which the bureaucracy was a privileged producer and user — a development integral to judges’ larger acceptance of agency-centered governance. Legislative history was, at least in its origin, a statist tool of interpretation.