<p>This research opens new pathways for validating young people’s creative expression as evidence suitable for climate decision making, across legal, policy and research contexts. In doing so, it seeks to advance the role of children and young people’s visual communication as a legitimate form of evidence. We argue that young people’s placards, carried at climate protests document the emotional labour (Hochschild, 2012) of young activists, and that collectively, they are a form of community evidence demonstrating young people’s expertise by experience (Kakade, 2023). To make this case, we draw on triangulated data from the Australian School Strike for Climate movement. We situate young people’s visual evidence within the International Court of Justice’s Advisory Opinion on the Obligations of States in respect of Climate Change (2025) (ICJ), which recognises the disproportionate impacts of climate change on children and young people. We make a case for how protest data can function as dual evidence, demonstrating that young people are both credible witnesses with real experiences of climate harm, and capable communicators who can translate those experiences into strategic political messages. The paper concludes by urging civil society and governments to pay more attention to this type of evidence if they are to genuinely understand what young people are experiencing and communicating. The paper issues a call to develop protocols that treat youth-generated visual evidence not as supplementary material, but as a legitimate and necessary contribution to climate justice.</p>