As voters are increasingly asked to decide complex health policy questions at the ballot box, new research from the Brown School at Washington University in St. Louis finds that healthcare-related ballot measures draw more voters to the polls and are more likely to pass than other initiatives — but they’re also especially sensitive to opposition spending by special interest groups.
The study, “Health Policy and Direct Democracy: Predictors of Successful Measures, 2010–2024,” forthcoming in the Journal of Health Politics, Policy and Law, analyzed 448 statewide ballot measures across 34 states, including 96 measures directly related to healthcare policy.
“Our findings show that healthcare policy stands apart in direct democracy,” said Caitlin McMurtry, an assistant professor at the Brown School and senior author on the study. “Voters are more engaged with these measures and more likely to approve them — but they’re also highly responsive to organized opposition.”
McMurtry and her co-authors, Cerise Siamof and Michael Youssef, both fourth-year medical students at WashU Medicine, found that healthcare-related measures had a higher passage rate than non-health measures — about 70% compared with 63%. After adjusting for other factors, healthcare measures were more than twice as likely to pass, and when “moral” issues such as abortion and physician-assisted death were excluded, healthcare measures were more than 3.5 times as likely to pass.
At the same time, campaign spending against a measure proved to be one of the strongest predictors of failure. For every additional $1 million spent in opposition, the odds of a measure passing dropped by roughly 8–10%, their study found.
“This raises concerns about equal representation: does money from special-interest groups help to educate voters or does it serve to protect corporate profits?” Siamof said.
The study also found that healthcare measures drew higher levels of voter engagement. Ballot completion rates, a measure of how often voters cast a vote on a given issue, were three times higher for healthcare ballot measures than for others on the same ballot, largely driven by controversial moral topics.
The authors suggest this heightened engagement reflects the personal and economic stakes of healthcare policy, which can range from insurance coverage and drug pricing to hospital operations and medical debt.
However, the research raises questions about whether voters are equipped to evaluate increasingly technical policy proposals. Unlike high-profile moral issues such as abortion, many healthcare ballot measures involve complex regulatory or financial details, such as provider staffing ratios, that voters may encounter for the first time at the ballot box.
“Voters are clearly paying attention to healthcare issues,” McMurtry said. “But many of these policies are highly technical, and it’s not always clear that voters have the information they need to make fully informed decisions.”
The study also highlights the growing role of interest groups in shaping health policy through direct democracy. Healthcare-related measures attracted significantly more campaign spending overall than other ballot initiatives, including substantial funding from industry groups seeking to defeat proposals that could affect profits.
The findings underscore the increasing importance of ballot initiatives in shaping U.S. health policy, particularly in states where legislative action has stalled.
“Direct democracy gives voters a powerful tool to influence healthcare policy,” McMurtry said. “But it also raises important questions about the role of money, voter understanding and the future of policymaking in the U.S.”
