One traditional justification for greater judicial deference to agencies on legal questions in the U. S. administrative regime is she expertise argument. This justification comports with traditional understandings about the respective roles of the different branches of government and agencies' place in modern government. Agencies, in this view, are the technical experts that put into operation the policy judgments made by legislators. Indeed, technical expertise is the raison d’etre of agencies by focusing on a particular regulatory field, or sector of the economy, agencies can do what Congress lacks the time and other institutional resources to do. Chevron VS National Resources, which presented the question whether the statutory term 'stationary source' referred to an entire pollution-emitting plant or, rather, to every single smokestack within such a plant, supplies an apt example of when an agency's special technical expertise can aid statutory interpretation. According to the expertise argument, agencies are deemed to understand even the legal ramifications of the problems agencies are created to work on. Admittedly, the dichotomy between legal and factual questions may at times be difficult to maintain, but that observation argues as much in favor of as it does against Chevron deference. Agency expertise, however, is not the only common justification. Sometimes the doctrine is justified also on democratic grounds. According to the argument from democracy, it is agencies, not courts, that are answerable to both the executive and the legislative representatives of the citizenry. Because judges are not elected, while presidents and legislators are, and because agencies but not judges are accountable to the President and to Congress, judicial deference to agency decisions enhances the political legitimacy of the administrative regime. Finally, Chevron may be justified also in the name of administrative efficiency or coordination. Before Chevron, different federal courts in different jurisdictions could interpret the same statutory provision differently. Multiple interpretations by different federal courts would mean that the statute 'said' different things in those different jurisdictions. Such confusion could be eliminated by appellate review, but agencies faced uncertainty pending review, and the possibility of different interpretations across different appellate circuits remained. Because multiple agencies do not typically interpret the same statutory language, however, Chevron deference allows the agency charged with administering a statute to interpret that statute. One agency, rather than many federal courts, now resolves ambiguities in the statute that the agency in question is charged to administer. Such interpretive streamlining not only reduces uncertainty but also promotes regulatory coordination. Once an agency has settled on a reasonable interpretation, it can act on the basis of that interpretation nationally. The expertise argument assumes that ______.