Despite decades of rising economic inequality across advanced democracies, political parties have largely failed to respond with meaningful policies. A new study published in the American Political Science Review sheds light on this trend, revealing that parties react to rising inequality but not to existing high levels of inequality.

The research, conducted by Alexander Horn, Martin Haselmayer, and K. Jonathan Klüser, analyzed over 850,000 party statements from 12 OECD countries between 1970 and 2020. Using a novel crowd-coded dataset, the authors distinguish between economic equality appeals and broader rhetoric around equal rights and anti-discrimination - often conflated in previous studies. Their new data show that economic egalitarianism declined from the 1980s to 2000, then rose again, while equal rights rhetoric steadily increased.

Key findings: left-wing parties increase their emphasis on economic equality when inequality is visibly rising, particularly when the income share of below-median earners declines. However, when inequality is already entrenched, these parties tend to de-emphasize redistributive policies. Right-wing parties, meanwhile, remain largely unresponsive regardless of inequality trends.

The authors identify three key reasons for this pattern. First, media coverage tends to highlight changes in inequality rather than persistent disparities, limiting public awareness. Second, high inequality suppresses voter turnout among low-income groups - core constituents of left parties - reducing electoral incentives for redistribution. Third, cognitive biases like system justification and meritocratic beliefs lead voters to accept existing inequalities as fair or inevitable.

Perhaps most concerning is the political silence surrounding the top 1% of earners. Despite their growing share of national income, no major party - left or right - appears to respond to this trend. The authors suggest this may reflect the invisibility of capital income, elite influence over policy, or the shifting priorities of left parties toward more affluent, educated voters.

The study concludes that inequality is not self-correcting in democratic systems. Instead, it follows a “ratchet effect”: parties may push back against rising disparities, but once inequality becomes entrenched, political incentives to reverse it fade.