With Act V of 1954 amending Act II of Budapest, the condition for ordering an investigation became the reasonable suspicion of a crime, and the investigation could be opened against a specific person if there was sufficient data indicating the identity of the perpetrator. If the person concerned was only a mere suspicion, he was not incriminated and could not be questioned before being charged.

According to Decree No. 8 of 1962 (I. Be.), no public prosecution could be initiated without an investigation, since “it was an accepted and widely held proposition that the investigation – i.e. the preparatory stage of the proceedings – is in principle equal and equivalent to the trial in terms of fact-finding, evidence and legal assessment.”3 However, the creation of the legal instrument of supplementing the denunciation has led to a separation between the beginning of the criminal proceedings and the beginning of the investigation. Criminal proceedings could be initiated only in cases of reasonable suspicion of a criminal offence and only against the person charged with the offence. The purpose of the supplementary report was to establish or exclude the existence of reasonable suspicion of the offence, with a view to minimising the number of proceedings initiated without justification.4 Noteworthy from the legal literature of the period is the view of Gödöny, who considered it a fundamental element of ‘socialist legality’ that the law should also define the scope of the facts to be proved in order to facilitate the activities of the investigating authorities.5 The socialist view of the law has, moreover, consistently taken the view that there is already evidence in the course of an investigation, and that the role of the investigating authorities is therefore at least as important as that of the courts.6 In the legal literature of the time, the view was generally held that, as a result of the evidence, “it is already possible in all cases to require of the investigator (prosecutor) an internal conviction with precisely the same objective basis – the force of certainty – as is always required of the judge.”7 Also noteworthy is the author’s view that the fundamental principle of investigation is planning,8 and that the various methods of criminal investigation are therefore of particular importance.

According to Act I of 1973 (Act II of 1973), a decision to refuse or order an investigation had to be taken within three days of the receipt of the complaint. An important twist in the Act was the reference to the ‘detection of the investigating authority’, based on the principle of exclusivity, which therefore left no chance for the process to continue without an investigation stage.9 This legislation made it a general obligation for all authorities to clarify the facts thoroughly and completely and to take into account incriminating and exculpatory circumstances, as well as aggravating and mitigating circumstances.10

On the basis of the above, it can be concluded that the significance of the Hungarian investigative profession cannot be considered uniform at all due to the different legal policy perspectives, and even with regard to the regulation of its dogmatics, there are significant differences in the procedural rules of the 19–20th centuries.