Background Social welfare legal problems impact negatively on mental and physical health. These include issues with welfare benefits, debt, homelessness, family and employment. Services providing legal assistance have developed collaborations with healthcare across the UK and the globe. These ‘health-justice partnerships’ aim to support health of the most disadvantaged groups, tackling interconnected challenges of health inequalities and access to justice. International evidence on the impacts of these partnerships has never previously been reviewed. This study interrogates the state of current evidence and provides new insights from international practice.

Methods A systematic scoping review of international literature was undertaken. Both academic and grey literature was included from OECD countries, 1995–2018. The review aimed to describe different service models and summarize evidence on impacts. Data from included publications were extracted and analysed narratively. Quality of included publications was assessed. Evidence on impact is presented according to each service objective.

Results Health-justice partnerships were diverse in their characteristics. Target populations focused on low income, vulnerable or underserved groups. Approaches to service coordination included co-location, referral, or integration of legal advisors into care teams and care pathways. The strongest evidence on impact was for increased access to legal assistance and improvements in individuals’ financial and social circumstances. Despite this role in addressing social determinants of health, evidence was lacking on the wider issues of prevention and health inequalities. There was strong qualitative evidence for improvements in mental wellbeing, reflected in some quantitative research. Studies suggested positive outcomes in supporting healthcare professionals and contributing to high quality patient care, although findings on healthcare utilisation and costs were mixed.

Discussion This is the first international review on the delivery of health-justice partnerships, bringing together evidence from across the world to map current knowledge on service models and impacts. Integration of health and legal services aligns with policy priorities in both sectors, addressing social welfare legal issues which are leading causes of inequality and underlying determinants of poor health. The evidence supports health-justice partnerships as a means of improving access to justice for vulnerable groups and alleviating health-harming legal needs. Some key service objectives require a stronger knowledge base, while others remain un-evidenced. Cross-sector alignment and collaboration presents challenges, and further research is needed on successful delivery of integrated services. This review has informed a primary research study exploring implementation of health-justice partnerships in different settings across England to inform future policy and practice.