The argument discussed by the authors of this work regards the precautionary measures of judicial mental hospital, with particular attention to the normative precept. After describing the historical genesis and reporting some theoretical criticisms concerning the precautionary measures and their application, they describe in details the numerous judgements issued, during the last decades, by the Constitutional Court (that, in a recent sentence did not miss the opportunity to underline the "inertness" of the legislator), emphasizing the extenuations of the distorsions generated by all those juridical norms based on the concept of "social dangerousness" (intepreted as the possibility for a person to commit a crime) and contained in the penal system of 1930, mainly founded on the ‹‹double platform›› punitive concept that provides both punishments and precautionary measures. For the reasons above this investigation has been done both considering the whole population of the acquitted for total vice (ex art. 222 of c.p.), hospitalized from the 1st of January to the 31st of December 2007 in the Judicial Mental Hospital of Barcellona Pozzo di Gotto (Me-Italy), and analysing all the data of the personal files kept in the Matricula Office, in the Treatment Area and in the Sanitary Direction. The aim of this research is to focalize the characteristics (such as age, education,occupational situation, previous offences, previous periods in a mental hospital or in a public organization, etc.) of the interned, the duration of their internment, and finally, the possible number of ordinances that extended the internment. The final results have been compared to those of a similar study developed by Russo (1987), on 232 incriminated acquitted for vice of mind, in the same Judicial Mental Hospital in 1987, and to some researches that took place in the Italian Judicial Mental Hospital during the last years.
