Gendered cooperation networks? Private members' bill co-sponsorship patterns in the Finnish parliament

Existing research highlights that gender—along with other identities—significantly influences legislative behavior. However, most studies focus on how gender shapes individual legislators' behavior, often overlooking its impact on relationships between legislators. Recent scholarship has emphasized the need to examine politicians' seniority to better understand gendered dynamics and behaviors in parliamentary settings. Building on this, our paper examines co-sponsorship networks of legislative bills to explore whether and how the presence of senior women among members of parliament (MPs) affects: (a) the structure of legislative networks, and (b) the substantive focus of these networks, particularly on gender-related bills. Although exploratory, the study draws on literature addressing homophilic networks—defined as the tendency to interact and form relationships with similar others—and theories of substantive representation to hypothesize about the influence of gender and seniority on collective legislative behavior. We anticipate that the interaction between gender and seniority significantly shapes MPs’ collaboration patterns. We explore our expectations in the context of the Finnish parliament, the Eduskunta, focusing on the co-sponsorship of private member’s bills (PMBs) from 1999 to 2015. PMBs are a popular instrument among MPs who use them for various reasons including policymaking and cultivating a personal vote. Prior research suggests that gender, and to a lesser extent seniority, are poor predictors of Finnish MPs' individual use of parliamentary instruments such as PMBs, speeches, and parliamentary questions. However, by moving the focus to the collective aspects (the cooperation networks), the paper sheds light on a process that receives only little interest although its importance for our understanding of parliamentary work and responsiveness: the ability of MPs to collaborate on designing and attempting to pass policy proposals. Hence, Understanding these networks not only reveals what can reach parliamentary policymaking but also how it does so. Ultimately, this paper contributes to understanding the broader implications of gender and seniority for the policymaking process.