Who carries out investigation for election-related criminal offenses?

Official website of the government of Monaco, “ThePublic Prosecution Department”, http://en.gouv.mc/Government-Institutions/Institutions/Justice/The-Public-Prosecution-Department

”The Public Prosecution Department of the Principalityof Monaco has the particularity of being the single Public ProsecutionDepartment for all of the Monegasque courts, before which the PublicProsecution Department is represented, which is where its French name ‘ParquetG?n?ral’ (meaning General Public Prosecution Department) comesfrom.  

[…]

In criminal matters, the Public Prosecutor receivesall complaints and allegations addressed directly to him, as well as thosefiled with the Monegasque police services, whose investigating police officerscome under his authority and who must send him their written statements andreports. 

Upon receipt of the complaints and allegations, thePublic Prosecutor determines the response they will receive.

Before making a decision, he may require the policeservices to undertake further investigations as part of a preliminary enquiry.”