The first Latino to win election to a seat in the U.S. Congress was Romualdo Pacheco, a Republican elected as a representative from California in 1877. (Several Latinos had previously served as territorial delegates, the earliest in 1822.) Latino members have been a constant presence in Congress since 1931, and in the House continually since 1943. Yet congressional scholars have given them and their impact on the institution scant attention.

In From Inclusion to Influence, Walter Clark Wilson seeks to remedy that omission. He provides a broad-gauged study of the role Latino members have played in Congress, particularly since the 1970s. Focusing on House members, because the number of Latino senators has been too few to allow for rigorous analysis, Wilson examines both the extent to which Latinos have been incorporated into the American political system and how successful they have been in having their interests represented in Congress. He overcomes two significant obstacles in this pursuit. First, even when looking only at House members, the number of Latinos serving in each session is relatively small, limiting analytical options. Second, much of the legislative process is opaque. Wilson is sensitive to both points; consequently he employs a range of research approaches, collecting data where possible and analyzing it with appropriate econometrics, and relying on interviews, case studies, and anecdotal evidence where useful quantitative data are not available.

The picture Wilson paints on the question of Latino political incorporation is fairly bleak, but still hopeful. He documents that the number of Latinos elected to Congress has increased slowly over time and that in recent years, they have started to gain positions of power, notably committee and subcommittee chairs. At the same time, consistent with the conventional wisdom, he shows that Latinos are still only elected from districts that contain substantial numbers of Latinos, that they are still mostly elected as Democrats, and that Latinos vote at lower rates than do members of other major racial and ethnic groups. All of this means that Latinos have yet to attain political power at parity with their numbers in society and may not for some time to come.

Wilson’s depiction of Latino success in having their interests represented in Congress is more positive. He examines the representational process in three slices. Initially, he looks at the relationship between representatives and the represented from two angles. The first is the extent to which representatives push Latino interests, defined as policies that disproportionally impact that group in a positive way. The second is the degree to which representatives embed distinctly Latino perspectives in their policy statements. Cleverly gathering and analyzing data on the content of press releases and congressional Websites, Wilson reports, as we might expect, that as the Latino proportion of a member’s district increases, Latino policy interests and perspectives in their public communications increase. More importantly, however, beyond the population effect, whether the representative is a Latino has an additional, independent, positive impact. Similar findings in regard to the number of Latinos serving on congressional staffs are also reported. Arguably, these are the most important findings in the book. It is often assumed or asserted that descriptive representation is important; here, the author is able to convincingly document it.

In the second slice, Wilson examines Latino representation and its impact on the congressional policy agenda. Again, the propensity to sponsor Latino-related legislation increases with the proportion of a member’s district that is Latino. And again, representatives who are Latinos exhibit a positive inclination to sponsor Latino-related legislation. Pushing harder on this topic, Wilson also finds that committee and subcommittee hearings chaired by Latino representatives are more likely to focus on Latino-related legislation than are hearings chaired by non-Latino representatives. Finally, he documents the role of the Congressional Hispanic Caucus in helping to set the congressional agenda on immigration policies. Overall, this second slice presents a picture of Latino influence in the legislative process that is consistent with the first slice.

The third slice, essentially what happened to Latino policy proposals, is the most challenging and least convincing set of analyses. Consistent with the first two slices, Wilson’s analysis of floor speeches reveals that the expression of Latino policy interests and Latino perspectives increases both with the percentage of a representative’s district that is Latino and with a representative who is Latino. But beyond investigating the content of “Dear Colleague” letters, the author is left confronting “the dog that didn’t bark in the night” problem that bedevils all studies of legislative outcomes. Positive outcomes in the American legislative process are rare, and demonstrating Latino influence in producing such outcomes is sufficiently challenging. But documenting that something did not happen because of Latino efforts is even more daunting.

In analyzing legislative outcomes, Wilson relies mostly on interviews and reconstructions of how various legislative proposals fared. He notes the occasional “small victories,” none of which should be dismissed as insignificant. Overall, the role of the Congressional Hispanic Caucus in determining outcomes is highlighted. But even when the caucus was unified, its greatest impact was limited to the brief period when the Democratic Party needed its votes to achieve a majority. When the Democratic majority was sufficiently large that the caucus’s votes were unneeded, its influence waned. And, of course, when the caucus was a small minority within the minority party, it exerted little influence in the legislative process.

As is always the case with any ambitious effort, there are things about this study with which some might disagree or where they might pursue it differently. For example, Wilson spends considerable time arguing that there is a cohesive Latino perspective and a set of Latino policies on which there is widespread agreement among Latino politicians. Other scholars might wish to explore the extent to which this is true or whether less generous definitions of what qualifies as Latino policies might change the findings. They might also examine whether Latino representatives whose families hail from different places and who themselves have had divergent kinds of life experiences (such as Cuban Americans in Florida) pursue their representational activities differently. Along these lines, the various career routes that Latinos have taken to arrive in American legislatures may warrant attention. There may also be concerns that Wilson’s work is somewhat time bound. His interviews, while insightful, are from 2006 and 2007, and the analyses are on data from the 109th and 110th Congresses. The potential problem is that much has changed in American politics since then, which might alter some of the conclusions drawn in this study.

With From Inclusion to Influence, Wilson has built a strong foundation for scholars to build on as they pursue studies on the impact of Latinos and other racial and ethnic groups in American legislatures. Legislative scholars will appreciate his thorough examination of Latino influence in the legislative process, going far beyond simply analyzing roll call votes. Wilson is also to be commended for his thoughtful contemplation of what legislative representation means and how it can be assessed.