Inmates are often vulnerable and exposed to various health problems. Public health and the commitment of society to social justice are two compelling reasons for the provision of health care in prisons. Guaranteeing the right of inmates to health depends on the interdisciplinary cooperation between criminal justice and health systems. The necessity of this interaction vests a key role in nurses in preserving optimal health in penal institutions. Considering the medical, social, and forensic dimensions of patients, nurses can play an effective role in establishing health justice and better welfare for inmates, their families, and society as a whole, while mitigating the adverse physical and psychological outcomes of confinement. The main question that this study aims to address is as follows: what are the role and position of forensic nurses in penal institutions? The research hypothesis is that the position of forensic nursing in Iran’s criminal justice system is structurally and institutionally different from those in Canada and the US. Hence, this study aims to explain the role and position of forensic nurses in the penal institutions of Canada and the US. For this purpose, a descriptive-analytical method was employed. According to the results, guaranteeing the right of inmates to health necessitates adopting novel solutions and attracting interdisciplinary cooperation. By engaging forensic nurses in penal institutions, Canada and the US have greatly succeeded in eliminating the shortcomings in this field. Therefore, it is suggested that Iranian authorities follow in the footsteps of the countries that have already taken this path and found promising solutions to deal with this problem and benefit from the capacity of nurses.