Nowadays, the alignment between public institutions, their practices and the Democratic Rule of Law paradigm must be more than an ideal, it must be a reality. However, in order to achieve this, old models must be abandoned and new ideas must be dared, without forgetting to take advantage of the experience already acquired. This work attempts to demonstrate the need to change the current model of Brazilian preliminary investigation, altering the beginning of criminal prosecution, in other words, the current Police Inquiry, and thereby enabling work that is in line with constitutional dictates, more efficient, impartial, free from manipulation and consequently of higher quality for all citizens.