Historically, police departments focused solely on criminal justice issues. Recently, there has been a dynamic shift in focus, with Law Enforcement professional groups assuming more responsibility for tackling mental health and distress-related issues (that may arise because of mental health related problems and learning disabilities) alongside Public Health departments. While Law Enforcement has become a ‘last line of support’ and an increasing partner in mental health support, there is partnership working between law enforcement, psychology, and health professions in training and mental health service delivery. The term vulnerability is frequently used across Law Enforcement and Public Health (LEPH) to identify those in need of these services. Effective vulnerability assessment is therefore expected to prevent unintentional harmful health and criminal justice consequences and manage the negative impact of such in cases where prevention is not possible. This scoping review aimed to identify how vulnerability is defined and assessed across LEPH organisations.