In this work, Cheryl Schonhardt-Bailey presents the culmination of her more than two decades–long study of the politics of the 1846 repeal of Britain's Corn Laws. Conceiving changes in the “three Is”—interests, ideas, and institutions—as the three central components of an explanation of this policy change, she presents a series of chapter-length studies focused on each of these elements. She further divides the chapters into “demand” and “supply” sections—with the former tending to emphasize the role of shifting interests, and the latter primarily devoted to discussions of ideology as revealed by parliamentary speeches. Like many who have preceded her, Schonhardt-Bailey studies very closely the proceedings in the House of Commons, but she breaks new ground by also studying the approval of repeal in the House of Lords. (That the latter chamber, dominated in 1846 by the landed aristocracy, would nonetheless not block repeal is even more remarkable than Prime Minister Robert Peel's success in the House of Commons.) She also examines the relationship between the discussion of repeal in local newspapers and the floor votes of members of Parliament (MPs)—a particularly apposite topic given the close relationship between these newspapers and the political parties of the day, and the lack at that time of any national news media.

For a question that has inspired substantial empirical research for several decades, it would be surprising and perhaps even a cause for concern if Schonhardt-Bailey's hypotheses and results were vastly at variance with previous work. They are not. Many of her specific results are broadly consistent with prior research on repeal. However, even then she generally has improved on previous work: She has gathered more data on MPs and their constituencies, her empirical model specifications are more encompassing, and overall she shows an admirable sensitivity to the breadth of approaches and theoretical perspectives employed by other scholars.

What is most distinctive about her argument is a claim that runs through all the chapters: The key to understanding the success of repeal was the ability of Prime Minister Peel to reframe the issue so that, at least for Conservative MPs, a second dimension was added. He did so by tying the preservation of Britain's conservative institutions to the necessity of giving ground to the middle and working classes on agricultural protection. The ironic effect of Peel's maneuver was to place his wing of the Conservative Party in the position of voting more in line with the demands of its constituents, thus appearing to abandon a Burkean view of the legislator as trustee of the public interest, rather than the agent of various constituency interests. In turn, this was easier for the Peel wing to do because, as Schonhardt-Bailey shows, the districts represented by Conservative MPs who backed Peel had weaker protectionist interests than those held by the Conservative opponents of repeal. As she notes, if one restricted consideration simply to the floor votes on repeal, one might be tempted to conclude that in this instance, the regression results suggest that ideology seemed to matter less. However, that result is an artifact of Peel's successful reframing of the issue for Conservative MPs.

The empirical evidence for this overarching claim does not cohere as neatly as one might wish. The sketch of a formal model of the new, higher-dimension issue space in Chapter 2 depicts a second dimension (“territorial constitution”), but it is not shown as orthogonal to the first, repeal-versus-liberalize dimension. The analysis of voting patterns in Parliament in Chapter 6 relies on Keith Poole and Howard Rosenthal's NOMINATE method, and finds that for floor votes in 1841–47, postulating a second underlying dimension improves the percentage of all votes correctly classified from 89.5% to 92.0%. Thus, the evidence for a stable second dimension underlying floor votes for this decade is weak. However, if the second dimension were created by Peel's actions only in 1846, then most of the votes comprising the sample are from a period that precedes the time when Schonhardt-Bailey claims that a second dimension had emerged. And if most votes other than the votes on repeal did not engage this second dimension, then those votes also would be satisfactorily classified without the need to add a second dimension to the model.

The most significant contribution that this book makes to empirical work—and not just on the politics of international trade—is its innovative use of computerized content analysis of parliamentary speeches. The author's method relies on word counts and word associations, both of which are quantifiable and amenable to statistical analysis—for example, using a variant of factor analysis to dimensionalize the clusters of associated words. Her identifying tags on each utterance (speaker, party, issue, time) allow her to link each distinct cluster to individual MPs, parties, and interests. The discourse space she shows is generally two-dimensional, with one dimension political-versus-economic. (The other dimension is not labeled). As she notes, there are several possible sources of the difference between the dimensionalization of utterances and that of floor votes; a complete understanding of the relation between the two will require more research.

Although the title suggests a work intended primarily for students of trade policy, From the Corn Laws to Free Trade will probably have the most impact on comparative politics. It speaks to the evolution of party systems by documenting the fracturing of the Conservative Party in Commons; advances studies of lobbying and legislative politics by exploring the role of local newspapers as an influence on MPs' votes; sheds light on the relation of ideology to material interests by tracing ideological themes in members' speeches and relating them to party, constituency, and historical context; and explores statistical and substantive questions raised by various attempts to “dimensionalize” a national political system. (By contrast, international events are generally a background factor). In its breadth of theoretical and methodological coverage, and its efforts to break new ground in theorizing about and empirically examining the connections among discourse, institutions, and interests, this is a pioneering work that deserves to have a wide readership.