International studies of aging processes recognized by the UN and the WHO as global agenda issues, which is associated with demographic, political, socio-economic, cultural, medical and criminological problems, caused by the increasing number of late age persons all over the world. These are issues of age discrimination trend, socio-economic stratification, cruel and dismissive attitude towards the elderly, their legal and social protection insufficiensy,'epidemic of dementia',which cause their vulnerability and victimization. The phenomenon of ageism, considering age as a synonym for “dementia”, may appear in general and forensic psychiatric practice, influence the accurate diagnosis and expert assessment, and through him, the rights of the elderly persons. A reflection of the marked socio-demographic trends is the increase in psychiatry of the number of 'gerontological' psychiatric examinations of patients with late age-related definitions of sanity, capacity to contract, legal capacity to act. Clinical and expert analysis of 235 later age patients (>60 years),who underwent forensic psychiatric examination in criminal and civil cases, helped to formulate the original concept of the understanding of aging processes (involution). It postulates normalization of gradual favorable aging and age-related mental norm of life, presumption of mental health, sanity, capacity to contract and legal capacity to act of elderly persons. It describes positive and negative forms of aging. It provides characteristics of adaptive regulatory mechanisms aimed at maintaining an optimal level of homeostasis, increased life expectancy, and evolutionary development of the elderly person. It describes the possibility of their deficiency if exposed to biopsychosocial factors in involution (involutive determinants) that are classified as biological, socio-psychological, legal and victimological.