New tree, growing forrest: Updating meta-analytic evidence on solidarity between U.S. people of color through an extension and partial replication

Published meta-analytic evidence shows that across five experiments, shared discrimination triggers solidarity between U.S. people of color (PoC), which then strongly correlates with support for pro-outgroup policies. Mini meta-analyses like these remain informative only if all conceptually similar experiments—regardless of statistical significance—are evaluated. We amend this meta-analytic record by adding a new study that only partially replicated the established solidarity pattern. Specifically, our study evaluated whether PoC solidarity encompasses Palestinian people: a racially stigmatized outgroup outside U.S. borders. We tested this through a pre-registered experiment with Black adults ( N = 851), the prototypical person of color. Unexpectedly, we find that exposure to shared discrimination with Palestinians insignificantly affected Black solidarity with PoC. This pattern arises despite exploratory analyses showing that PoC solidarity incorporates Palestinian people. Nevertheless, we still find that Black camaraderie with PoC strongly correlates with pro-Palestinian attitudes, which reaffirms prior work. Finally, with this partial replication included, we meta-analyze all six available solidarity mechanisms through a random effects model. This analysis reveals that PoC solidarity remains a viable mechanism behind inter-minority solidarity. Our results have implications for PoC solidarity and the regular updating of meta-analytic evidence in political science.