Australia's national laws for worker psychological health: a policy evaluation and psychosocial safety climate analysis

• A multi-study evaluation showing psychological health work health and safety (WHS) regulations in Australia increased organisational Psychosocial Safety Climate (PSC). • Study 1 uses expert reports (2021-2024) from 19 countries to confirm Australia’s increased legislative focus on work-related psychological health. • Study 2 is a quasi-experimental study using national data sets to show significant increases in PSC in jurisdictions. • Study 3 is a longitudinal sector study that shows sustained improvement in PSC and reductions in psychological distress following the introduction of the new WHS regulations. Improving workers’ psychological health is an international priority. This multi-study policy evaluation research integrates institutional and organisational theory to determine if—and why—the introduction of enhanced pro-worker psychological health law (Work Health and Safety [WHS] Regulations) within a country (Australia) can lead to impact in organisations within jurisdictions (i.e., regions) and industry sectors. We assess organisational impact via changes in Psychosocial Safety Climate (PSC), which captures perceptions of the organisational safety system for worker psychological health, as well as worker psychological distress. Study 1 explores the international legal context, using expert reports from 19 countries to assess national work-related psychological health law development between 2021 and 2024. Results verify that Australia had an increased legislative work-related psychological health focus. Study 2, a quasi-experimental design, using large national data sets, compared jurisdictions within which the national law was implemented in 2023 (Legislated group) or not (Comparison group). Significant group-by-time interaction effects were found for PSC, aligning with expectations whereby PSC increased significantly in the Legislated group. Study 3, a longitudinal field experimental study explored the reach of the legal changes in a specific industry sector (university). With three-waves of data (n = 339), comparing universities across different jurisdictions, a group-by-time interaction was found for PSC and psychological distress. Findings show a positive impact of targeted psychosocial law on organisations’ safety system and workers’ health. The current study provides a theory-driven framework for evaluating and explaining legislated policy effects—across jurisdictions and within sectors—showing it can be a wide-reaching lever for improving work conditions and psychological health in the longer term.