BACKGROUND: As drug checking becomes more integrated within public health responses to the overdose crisis, and potentially more institutionalized, there is value in critically questioning the impacts of drug checking as a harm reduction response.

METHODS: As part of a pilot project to implement community drug checking in Victoria, BC, Canada, in-depth interviews (N = 27) were held with people who use or have used substances, family or friends of people who use substances, and/or people who make or distribute substances. Critical harm reduction and social justice perspectives and a socioecological model guided our analysis to understand the potential role of drug checking within the overdose crisis, from the perspective of prospective service users.

RESULTS: Participants provided insight into who might benefit from community drug checking and potential benefits. They indicated drug checking addresses a "shared need" that could benefit people who use substances, people who care for people who use substances, and people who sell substances. Using a socioecological model, we identified four overarching themes corresponding to benefits at each level: "drug checking to improve health and wellbeing of people who use substances", "drug checking to increase quality control in an unregulated market", "drug checking to create healthier environments", and "drug checking to mediate policies around substance use".

CONCLUSIONS: Drug checking requires a universal approach to meet the needs of diverse populations who use substances, and must not be focused on abstinence based outcomes. As a harm reduction response, community drug checking has potential impacts beyond the individual level. These include increasing power and accountability within the illicit drug market, improving the health of communities, supporting safer supply initiatives and regulation of substances, and mitigating harms of criminalization. Evaluation of drug checking should consider potential impacts that extend beyond individual behaviour change and recognize lived realities and structural conditions.