In the conceptual history of abnormal personality, in today's diagnostic nomenclature Personality Disorder, there has always been a large amount of overlap between issues of psychopathology and issues of dissocial behaviours. This is one reason why in this field there are close connections between sociological, political and psychiatric approaches. The dissent of irresponsibility because of insanity, which is clearly acknowledged for true mental disorders, is put in question in the realm of personality disorders in many countries and legal systems. There are also different modalities how to deal with abnormal types in the legal systems. During the process of unification in Europe the rulings of the “European Court for Human Rights” has become of major impact. This has led to a severe controversy with higher courts in Germany, concerning the question of detention for highly dangerous persons in security institutions. Diagnostic decisions and the validity of ICD-10- and DSM-categories for judgements in forensic psychiatry and in court are at present heavily debated. In this paper I will discuss the consequences of diagnostic concepts for legal and forensic decisions.