On the relationship between the Public Prosecutor and the Criminal Police.
The Code gives the Public Prosecutor an active role as a leader of preliminary investigations.
Firstly, the Italian Public Prosecutor can actively search informations relating to the offence (notitiae criminis), and not just passively receive information provided by the police (Article 330).
Secondly, when he finds or receives a report of a criminal offence, he leads the investigation and directs the criminal police (Article 327).
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Under the old Code, there was a very feeble link between the Public Prosecutor and the criminal police. Consequently, in 1988, to give effect to Article 109 of the Italian Constitution*, the new Code completely modified the relationship between these subjects.
In terms of personnel relations, criminal police officers and officials report to the criminal police corps they belong to, and, ultimately, to the competent Ministry ...; but the Code has strengthened the functional dependence of criminal police upon Prosecutors. {This includes but is not limited to police departments at the disposal or attached to each Office of the Public Prosecutor of the Republic (CPP Article 58).} The members of these departments are police officers, who can only play a criminal investigation activity and the Public Prosecutor can command them (CPP Article 59).
Also, there are the following procedural laws:
CPP Article 55 Functions of criminal police
1. The criminal police shall, even on its own initiative, receive notitae criminis {a notice conveyed to a prosecutor that a crime is alleged to have occurred}, prevent offences from producing further consequences, search for offenders, take any measures necessary to ensure sources of evidence and collect any other material which may be needed for the application of criminal law.
2. The criminal police shall carry out any investigation and activity ordered or delegated by the judicial authority.
3. The functions referred to in paragraphs 1 and 2 shall be carried out by criminal police officials and officers.
CPP Article 56 Criminal police units and departments
1. Criminal police functions shall be carried out under the supervision and direction of the judicial authority by:
A) criminal police units as established by law;
B) criminal police departments established at each Office of the Public Prosecutor of the Republic and made up of personnel from criminal police units;
C) criminal police officials and officers belonging to other bodies required by law to carry out investigations after receiving a notitia criminis.
CPP Article 326 Purposes of preliminary investigations
1. The Public Prosecutor and the criminal police, within their respective responsibilities, shall conduct the investigations necessary for deciding to conduct a criminal prosecution.
CPP Article 327 Management of preliminary investigations
1.
The Public Prosecutor shall manage investigations and the criminal police shall be at his direct disposal. Even after notifying the notitia criminis to the Public Prosecutor, the criminal police shall continue to carry out activities on its own initiative following the procedures described in the Articles below. {The "Articles below" are Articles 347 - 357; for example, Article 350 Investigative questioning of the suspect, allows for the police to question a suspect who has not been arrested, but the police must follow the procedure of Article 64 and require the suspect to retain a lawyer prior to questioning and conduct the questioning only in the presence of the lawyer (CPP Article 350.3). If the person is questioned as a witness, CPP Article 351 applies, and also Article 63, regarding incriminating statements.}
*Art. 109, It. Const.
The judicial authorities have direct use of the criminal police._____
Conclusion:
The activities of the criminal police are managed and directed by the Public Prosecutor in an investigation, but the police may carry out some activities on their own initiative as well. This applies to all the police working on the investigation, and not only to those who may be at the disposal of the Office of the Public Prosecutor.
The Italian Public Prosecutor has the status of a magistrate and thus part of the judicial authority.
Source:
Gialuz, Luparia, and Scarpa, eds. The Italian Code of Criminal Behavior: Critical essays and English translation, Wolters Kluwer Italia (C) 2014, p. 23, 25 - 26