Abstract

Objectives: Psychological diseases are currently some of the most common diseases, as a result of many organic and social factors. Those diseases affect man and his mental and physical powers. This effect may extend to deficient or no perception and will that make man unable to control his acts and, accordingly, can’t be punished for the crimes that he commits while under the effect of those diseases because they bar penal liability and reduce it, in accordance with the conditions of each of them. Methods: The researcher mainly applied the inductive methodology of research to present the subject of the study. He also applied the comparative methodology in some parts to draw some conclusions that produced number of recommendations that we hope they can contribute to the legislative system of the Sultanate. Conclusions: The study reveals that mental illnesses predominantly affect the elements of criminal responsibility (awareness and will), and this impact varies depending on the type of illness. Some illnesses lead to the loss of these elements, while others only diminish them. Through this research, we observe that legislators have set conditions and criteria for exempting the criminal responsibility of the psychiatric patient. This makes it difficult or nearly impossible for an ordinary person to benefit from such provisions. Additionally, legislators have balanced the proportion of the illness's impact on the psychiatric patient and the criminal responsibility in cases where awareness and will are lacking at the time of committing the crime. In such cases, responsibility is proportional to the level of awareness and will be possessed by the perpetrator.