Welcome! I am an Assistant Professor of Political Science in the School of Public and International Affairs at the University of Cincinnati. I study American legislatures, with a particular focus on Congress, campaigns and elections, and identity. I specialize in quantitative methods and use big data, machine learning, and causal inference in my research. My work is published in outlets such as Political Research Quarterly, PS: Political Science & Politics, and State Politics & Policy Quarterly.
I received my Ph.D. in Political Science from the University of Virginia in 2025. Before UVA, I earned a B.A. in Politics and International Affairs, with a minor in Poverty Studies, from Furman University.
Publications
I’m Coming Out! How Voter Discrimination Produces Effective LGBTQ Lawmakers
Jacob M. Lollis and Mackenzie R. Dobson.
PS: Political Science & Politics, 2025.
PDF DOI Replication
Abstract
Are LGBTQ legislators effective lawmakers? We build on theories that link voter discrimination to legislative effectiveness by arguing that voters’ biases against LGBTQ candidates narrow the candidate pool, leading to the election of only the most experienced and qualified LGBTQ candidates. As a result of this electoral selection effect, we expect that LGBTQ legislators will be more effective lawmakers than their non-LGBTQ counterparts. To test this, we combine data on state legislators’ LGBTQ identification with their State Legislative Effectiveness Scores (SLES). Our findings reveal that LGBTQ legislators are meaningfully more effective than non-LGBTQ legislators. To link our findings to voter discrimination, we leverage over-time variation in discrimination toward LGBTQ individuals. Across four tests, we consistently find that LGBTQ lawmakers elected in highdiscrimination environments are more effective than those elected from less discriminatory environments.
Race, Contact Effects, and Effective Lawmaking in Congressional Committee Hearings
Jacob M. Lollis
Political Research Quarterly, 2025
PDF DOI
Abstract
Though there is strong evidence that nonwhite lawmakers introduce more racially salient legislation than white lawmakers, it is less clear whether race is a significant predictor of other legislative behavior. Given mixed findings in existing research, lawmakers’ actions in committee offer a new test of how race shapes legislative behavior. I develop new, original measures identifying race references in more than 1.4 million congressional committee hearing statements. I find that nonwhite lawmakers discuss race more frequently than white lawmakers in hearings, though white lawmakers are more likely to mention race in racially diverse hearings due to contact effects. Using a novel measure of race-issue bills, I demonstrate that lawmakers’ race statements in hearings are linked to policy representation. These findings explain how racial diversity in legislatures affects legislative speech and policy representation.
Are Workers Effective Lawmakers?
Jacob M. Lollis
State Politics & Policy Quarterly, 2024.
PDF DOI Replication
Abstract
Are workers effective lawmakers? Throughout American history, some politicians and elites have argued that white-collar Americans are more qualified than working-class Americans to govern. To date, however, we know relatively little about the legislative effectiveness of working-class lawmakers. I develop a theory of class-based electoral selection that links class-based discrimination in elections to legislators’ performance in office. I argue that working-class candidates face class-based biases in elections that make it more difficult to emerge and successfully win elective office. As a result, I expect the working-class candidates who do become lawmakers to be equally or more effective than their white-collar colleagues. To test these expectations, I create a data set merging the occupational background of more than 14,000 individual state legislators with their state legislative effectiveness score (SLES). The resulting data set includes more than 50,000 state legislator-term specific observations. Consistent with my expectations, I find that working-class lawmakers do not underperform white-collar lawmakers. Further, I provide evidence that, across various models and specifications, the gap between working-class and white-collar legislators’ effectiveness is negligible.
Nothing to See Here: Republican Congressional Members’ Twitter Reactions to Donald Trump,
C. Danielle Vinson and Jacob M. Lollis
Congress & The Presidency, 2023.
DOI Replication
Abstract
How do co-partisans respond to the President on Twitter? This article examines whether and how Republican legislators reacted to President Trump in five instances when he broke with Republican Party policy positions or norms. We theorize that legislators’ electoral environment, constituency, and identity shape their response to the president, and we test our hypotheses using nearly 2,500 hand-coded tweets from Republican legislators between 2018-2020. The overwhelming reaction by Republican legislators to Trump’s actions was to ignore him. When members did react to the president, their response was primarily driven by their electoral environment and identity. Those from the most Trump supportive districts supported the president, and retiring members were most likely to oppose him. Male legislators were much more likely to support and oppose the president, while female legislators mostly ignored him. And, if they reacted, the most ideologically extreme Republicans were more likely to support than oppose the president. The implications of these findings are troubling. Even when President Trump violated traditional norms or deviated from long held party positions, his congressional co-partisans remained silent, occasionally offering support but rarely opposition.
Working Papers
Congressional attention to abortion after Dobbs
Jacob M. Lollis and Mackenzie R. Dobson
Status: Pre-Review
Paper
Abstract
The Supreme Court’s 2022 decision in Dobbs eliminated the federal constitutional right to abortion. Existing work examines how the decision affected voters’ attitudes and candidates’ campaign strategies, but legislators’ reactions remain understudied. We argue that legislators increased their attention to abortion after Dobbs only when gendered representational incentives and party-based electoral incentives aligned. For female Democrats, these incentives reinforce one another, jointly encouraging greater attention to abortion. Female Republicans, however, face gendered representational considerations that encourage attention to abortion, while party-based incentives make such attention electorally costly. Among male legislators, partisan incentives alone are insufficient: although male Democrats have a party-based incentive to increase attention, they lack a gendered incentive. We test this argument by identifying abortion references in nearly 1.6 million statements from U.S. House committee hearings. Difference-in-differences (DiD) estimates show no pre-Dobbs gender or party differences; after the decision, however, female Democrats durably increased their attention to abortion relative to female Republicans, with no change among male legislators.
Learning in Committee: How Racial Diversity Shapes Speech, Evidence Use, and Substantive Representation in Congress
Jacob M. Lollis
Status: Under Review
Paper
Abstract
Although increased racial diversity has expanded congressional attention to race, we know little about how committee diversity shapes interactions between nonwhite and white legislators—or whether those interactions alter behavior. I argue that in racially diverse committees, white Democrats learn from nonwhite colleagues, leading them to make more evidence-based claims when discussing race. To test this expectation, I combine large-scale text classification with a detailed content analysis of more than 11,000 race-based committee hearing statements and 87,000 full bill texts from the 105th–117th Congresses. Using a within-legislator identification strategy, I find that white Democrats are more likely to reference evidence when discussing race in diverse committees and to cite the same sources as their nonwhite colleagues. I also demonstrate that race-based expertise facilitates substantive representation, as legislators with such expertise are more effective at advancing race legislation. These findings demonstrate that descriptive representation fosters substantive representation in part through identity-based learning in legislative committees.
The Concentration of Legislative Effectiveness in the American States
Jacob M. Lollis and Todd Makse
Status: Under Reveiw
Paper
Abstract
Research on legislative effectiveness has largely focused on individual-level traits that promote policymaking success. In this paper, we shift attention to how lawmaking success is distributed in state legislatures. We theorize that institutional rules and chamber characteristics shape whether effectiveness is concentrated among few lawmakers or more evenly shared across a chamber’s members—and examine how this variation influences legislators’ behavior. We identify three key findings. First, the distribution of policy success varies widely across chambers and is most concentrated on consequential legislation. Second, smaller chambers and chambers that limit bill introductions are associated with more dispersed lawmaking success. Third, new legislators adapt their collaboration strategies in response to the concentration of effectiveness. These findings highlight the interplay between individual lawmaking effectiveness and the institutional environments in which they operate.
Why Citizens Dislike Professional Legislatures: White-Collar Government and Policymaking for the Wealthy
Mackenzie R. Dobson, Jacob M. Lollis, Jeffrey J. Harden, and Justin H. Kirkland
Status: Under Review
Paper
Abstract
The steady professionalization of American state legislatures has created a key tension in political representation: citizens disapprove of professionalized legislatures, on average, yet those legislatures are best equipped to represent their policy preferences. We explain this paradox by arguing that citizens’ disapproval stems from distrust of white-collar legislators—who are overrepresented in professionalized chambers—and their policy priorities, rather than from opposition to institutional reforms that enhance legislative capacity. Using data from a pre- registered conjoint experiment and temporal observational analyses, we find that citizens do not oppose the institutional expansion of legislative capacity. Rather, they react negatively to representation from white-collar lawmakers, whom they associate with professionalized legis- latures. Further, we demonstrate that this opposition is justified; income inequality and poverty have increased with professionalism over time. These findings challenge existing accounts by suggesting that disapproval of professionalism is a rejection of governing by economic elites—not of reforms intended to support legislative capacity.