The public prosecutor is the key person in the pre-trial proceedings, as he governs the procedures at this stage and instructs the police authorities, i.e. supervises the work of investigator. The public prosecutor is the only person entitled to overrule decisions and measures carried out by the police authority and replace them with his own. If need be, the public prosecutor also has the sole right to carry out particular actions in the proceedings, or even the entire investigation.

Further, the public prosecutor is entitled to decide on release from imposed custody. His/her approval determines many essential steps. The public prosecutor may also decide to discontinue the prosecution, to approve a settlement (also leading to discontinuation of the prosecution) or to approve a conditional discontinuation of the prosecution.

Depending on the collected evidence and the position of the accused, the defense strategy may be to remain silent ("prove me guilty or stop the prosecution"). By contrast, the defense may employ a method of effective communication with the public prosecutor. Under certain circumstances, this may be crucial for a favorable outcome for the accused. 

A criminal report is a private motion directed at the public authority to exploit the information provided to investigate, on an official duty, whether and by whom a crime has been committed.

The filing of such a report is not determined by formal requirements. Therefore, a criminal report can be filed in various ways, for example, orally in a protocol (at any police station), in writing, electronically, or even by telephone.

Such a report can be filed not only by any person (natural or legal entity), but by public authorities as well. A criminal report may be filed at any criminal proceedings authorities (at a public prosecutor's office and at a court in addition to a police station). However, for the fastest initiation of the investigation stage, it is usually most effective to file the criminal report at the competent police authority.

Only the criminal proceedings authorities are entitled to identify the perpetrator and all the circumstances. The investigation does not depend on the further activity of the person who filed the report. In general, it is advisable for the complainer to fill the report against an unknown perpetrator (providing only objective information that indicates a possible perpetrator), so that the complainer avoids the risk of prosecution for a false accusations if the "targeted" criminal report is not proven.

It is particularly advisable that the report should contain only relevant information and be supported by the appropriate documents, if need to be. Doing so shall facilitate the work of the criminal proceedings authorities and increase the probability that the filled report will be profoundly verified. 

Once a criminal report has been filed, the police authorities begin to summon other persons from whom they can reasonably expect to obtain information for the pre-investigation stage in order to verify the suspicion of a criminal offence.

Once the charges have been brought, i.e. at the investigation stage, interrogation is required (rather than a simple explanation). If the accused is questioned, he/she has a completely different range of rights, including the right to refuse to testify altogether. By contrast, the right to refuse to submit the required explanation is limited.

The summoned person is obliged to submit the explanation under threat of coercion (by imposing a fine or bringing to the police authority by force), but he/she may refuse to submit only if it would endanger with prosecution himself/herself or a person relative to him/her (defined as persons "whose harm he/she would perceive as his/her own harm"). The person who has provided the explanation has also the right to check out the record of the given explanation and, after confirming it, to receive a copy of it.

Although upon the submitted explanation nobody can be convicted (the content must be repeated at a later stage of the criminal proceedings as the testimony), the provision of the explanation is dangerous to underestimate and therefore must be realized with the utmost caution, which includes an advantageous employment of attorney's presence.

For the purpose of criminal proceedings a person may be detained. This is known as detention: a restriction of personal liberty for a very short period of time at the police authorities' discretion. Detention can only occur if certain legal standards are met. Upon employment of detention, the police authority is oblidged to immediately notify the supervising public prosecutor to execute the interrogation of the detainee, recorded in official protocol.

The detention may last no longer than 48 hours. If, upon on the supervising public prosecutor's request, the court does not decide to take the accused into custody, then the accused must be released at once. The judge must hear the detainee within 24 hours of when the request was received, hence, the court operates even outside regular working hours.

Beyond persons, the police investigator (upon the consent of supervising public prosecutor) may also seize any item using one of two procedures, depending on its type: (1) to submit and confine items used for evidence and (2) to confine items, which served as instrumentals of crimes or are a yield on crimes.

An item deemed important for criminal proceedings may be seized upon at least one of the following conditions: 1. the item can be used for evidence, 2. the item was intended or used to commit the crime, 3. the item was obtained by the crime, as a reward for the crime, or exchanged (even in part) for another item obtained by the crime or as a reward for the crime, or 4. the item is of a substitute value for an item defined in points 2 or 3.

In order to rightfully seize, it is not nescesarry for the police authority to collect unambiguous proof that the item fulfills one of conditions above. If the collected facts imply that the item was involved in the crime, the condition for seizure has been met. Following the seizure of items, the criminal proceedings authorities are responsible for their maintenance and conservation. If the seized items become damaged during the criminal proceedings, the possessor is entitled to claim compensation from the authorities (reasoned by the insufficient care of the seized items).

The house search is a method to collect evidence in criminal proceedings. The execution of a house search is considered to be an "urgent and non-repeatable action" in the pre-investigation phase of criminal proceedings.

Therefore, in order not to violate the constitutional right to privacy within the home, the house search must fulfill strict conditions. These conditions defined in very general terms in the Criminal Procedure Code, and have gradually been clarified by the Constitutional Court. According to these definitions, one of the three following situations must occur to justify a house search: 1. the perpetrator is unknown, but the search is necessary for further criminal proceedings, 2. the perpetrator is known, but at the time of the search it is impossible to inform him of the grounds for criminal proceedings, or 3. there is already sufficient evidence against the perpetrator to initiate criminal proceedings without the house search, but there is a reasonable concern the perpetrator may destroy available evidence following the charges.

If the house search is imminent, it is good to know the rights and duties of the person concerned, in particular what cooperation he/she must provide to the criminal proceedings authorities. The evidence seized in the house search may be crucial to the outcome of the criminal proceedings.

Criminal proceedings begin with the issuance of the charge. It is necessary to submit a complaint against the decision to begin the criminal proceedings within three days. This complaint can play a key role in whether or not the accused is eventually brought to trial.

An outline of the complaint must be submitted within the three-day period. However, its grounds may be supplemented within a certain granted time period provided to the accused, particularly after the accused can study his criminal case file and/or, discuss the the charge and the contents of the file with his defense attorney who then prepares a detailed grounds for complaint.

While detention may occur before the charges are brought against the accused, custody may occur only after that. The imposition of custody temporarily deprives the accused of his/her personal freedom and forces him/her to stay in the custody of the prison. During the criminal proceedings it is not automatically required that custody is employed. The imposition of custody is not based on seriousness of the prosecuted crime, but the reasonable concern that one of the following 3 situations may occur:

1. the accused will hide or flee to avoid the prosecution or the sentence,

2. the accused will influence the co-accused or witnesses,

3. the accused will continue or repeat the criminal act(s) for which he/she is currently being prosecuted (or has been prosecuted in the past).

Both the judge and the defense attorney must be present when the imposition of custody is determined. The defendant's behavior is extremely important at this time. The support of a defense attorney is also of key importance, as he is able to legally refute the existence of grounds for custody or provide for a custody substitution – e.g. a bail in an amount set by the court, a written promise from the accused, a guarantee from another person, or a proposal of supervision by a probation officer. The judge shall decide on the acceptance of any of these alternatives during the custody imposition proceedings.

If the court imposes the custody, the defense attorney is entitled to reach an agreement with the public prosecutor to substitute the custody for one of the above-mentioned alternatives if the alternatives were impossible to employ during the custody imposition proceedings at the court because of the extremely short due time for collection of the required documents. Even in the case of a court-imposed custody, the accused can be released from the custody very fast by this procedure.

The Constitution establishes the prohibition of self-incrimination. Therefore, the accused has therefore the right to give a testimony, but not the duty. The accused may also testify only partially. Additionally, if need be, the accused can choose to cooperate with criminal proceedings authorities by giving a detailed testimony in return for the possibility of a dismissal of the prosecution or a reduced sentence.

The choice of strategy must be made in advance, based on the detailed knowledge of the charge and the contents of the case file, i.e. knowledge of what the person is accused of and what the authorities are able to substantiate as well as knowledge of the accusation – not only at the time when charges were issued but also subsequently during the criminal proceedings.

Although the content may be the same as the submission of the explanation, following the issuance of charges, explanations must be repeated or deepened as a witness testimony. The testifying person therefore has the legal status and the corresponding rights of a witness (including the claims to witness recompense).

The witness may only fail to provide testimony if doing so may cause a criminal prosecution to him/her self or to a person relative to him/her. If the witness does not have these grounds, he/she may be compelled to give testimony by imposing fines. However, he/she cannot be compelled to provide details, e.g.the witness only has to give testimony only about what he remembers without any doubt.

An important means for the accused (and his/her defence attorney) to influence the pre-trial proceedings in favor of the accused (to avoid the indictment) is to have comprehensive knowledge of the investigation's development. This can only be legally realized by unrestricted access to the case file, which cannot be denied to the accused and his attorney. However, access to this file may be denied to other persons.

It is important to note that there is an official and unofficial part of the case file, the division of which is solely in the hands of the public prosecutor. The public prosecutor is responsible for deciding which of the information obtained during the criminal proceedings is related to the indictment and which is not (they will be nevertheless archived by the police).

The quality of the defense attorney is determined by how he proposes to supplement the investigation, i.e. the search for additional evidence in favor of the accused. The aggrieved party also has the right to propose supplementation to the investigation. The public prosecutor has absolute power to approve or reject such proposals; if he/she rejects the proposals, the only remaining opportunity to supplement evidence is at trial.

To discontinue criminal proceedings means to end the prosecution of the accused without indictment. Discontinuation of criminal proceedings occurs at the discrection of the public prosecutor once he/ she has reliably established that either (1) the crime did not happen, (2) the act is not a crime, (3) the accused did not commit the crime, (4) the criminal proceedings are inadmissible because the accused was not sane at the time of the commitment of the crime and therefore was not criminally liable, or (5) the punishability of the crime has expired.

A futile criminal proceeding ending in discontinutation may cause claims of the prosecuted to arise against the state. These claims may include the rights to compensation for wrongful prosecution or delays in proceedings.

Although it is well known the outcomes of criminal proceedings are usually imprisonment, in recent years, the focus of punishment is shifting to alternative resolutions of criminal proceedings known as diversions.

The most familiar diversion is 1. the plea bargain (agreement on the guilt and punishment), but there are also others, such as: 2. the criminal order proposed by the public prosecutor (issuing a criminal order results in a reduced, shortened procedure, however, if the accused wishes to stand trial, they may do so by issuing a dissent in due time), 3. the conditional discontinuation of criminal proceedings (which is widely used for minor offences), 4. settlement (a settlement is allowed by the court upon not only the consent of the aggrieved party, but also the recompense and a contribution to a fund for the victims of crimes), and 5. the withdrawal from criminal proceedings as a minor.

Both the accused and the public prosecutor may propose any form of diversion (the aggrieved party may not propose), however, the final decision about the proposed diversion is always at the discretion of the public prosecutor. Any of the diversions may also be proposed at the beginning of the trial. If proposed, the court either approves the diversion or disapproves and continues the trial.

For offences that belong to the jurisdiction of the lowest district courts and for which a maximum sentence of 3 years imprisonment may be imposed, the summary pre-trial proceedings may be executed. However, for this procedure to occur, at least one of the following condition must be fulfilled: 1. the police must have detained the offender at the offence (or immediately afterwards), or 2. the investigator has established facts justifing the initiation of criminal proceedings and there is a possibility to bring the offender to trial within 2 weeks from the date the investigator received the criminal report.

The pre-trial proceedings end with the filing of the indictment. Once the indictment is filed, it should be clear exactly what the defendant is accused of and what his proposed punishment entails. The opportunity to negotiate deflections with the public prosecutor also ends with the filing of the indictment, as does public prosecutor's ability to approve deflections without the court's approval. Hence, the criminal proceedings enter the trial stage.