The beginning of the investigation

When the law enforcement authorities become aware of a possible criminal offence – and if, where necessary, a request to prosecute has been filed – they are obliged to follow up on this suspicion. Thus, in many cases, investigative proceedings begin when a criminal complaint is filed with the police or the public prosecutor's office. However, a criminal complaint is not mandatory. If the police become aware of a possible criminal office by other means, for example in the context of other investigations, they must also follow up on it.

Initial suspicion

A mere assumption is not sufficient for initiating an investigative proceeding against a person. There must be sufficient factual indications of a criminal offence, i.e. there must be a possibility that a criminal offence has been committed. Moreover, no investigation may take place if the conduct in question is not punishable, but rather, for example, merely immoral or disturbing. It is thus possible that careful examination of a criminal complaint will be enough for the public prosecutor’s office to decide against initiating an investigation.

In order for the police and the public prosecutor's office to be able to examine whether a criminal offence has been committed, they need information about the offence which is as specific as possible, ideally first-hand information. For this reason, witnesses must generally make their statements orally or in writing. The sooner the police become aware of a criminal offence, the faster they can act and find evidence likely to clarify the facts of the case.

A criminal complaint may be filed either in writing, e.g. by post or to an online police station, or in person at a police station. In the latter case, the person concerned is, of course, allowed to be accompanied and supported by other persons. If a person can specify witnesses, he or she should state their names and addresses at this point.

• At the beginning of an investigative proceeding, the persons affected by a criminal offence are questioned, which means that they are then witnesses as well. This confers both rights and obligations on them.
• Witnesses must tell the truth. This is because their testimony may subsequently have a decisive influence on the further course of the proceedings.
• If a person is investigated to whom you are or were married, or to whom you are engaged, you do not have to testify. The same applies if you are closely related or related by marriage to the accused person. Even if your family relationship with that person is more remote, you should mention it. In addition, you do not have to answer any questions if you would incriminate yourself or relatives by doing so. The person questioning you is obliged to clarify whether you can exercise your right to refuse testimony in this case or not.
• Detailed information on your rights as a witness can be found here.

What else do the police and the public prosecutor's office do?

In addition to questioning affected individuals and witnesses, the police are responsible for securing possible evidence left by the suspect. This may include fingerprints, skin particles or indications of physical injury inflicted on victims. The police can also carry out further investigative measures, such as conducting searches, seizing documents or obtaining information from public authorities; where serious criminal offences are concerned, intercepting telecommunications might also be an option. In that process, the police cooperate closely with the public prosecutor's office or the investigating judge.

Certain decisions at the investigative stage are taken by the investigating judge. This is because such matters must be determined by a judge. This includes, for example, deciding on the issuance of arrest warrants.

In specific cases, investigating judges also conduct video examinations of witnesses affected by a criminal offence as part of the investigative proceeding. Such video examinations usually take place in a protected setting. The idea is that witnesses subsequently do not have to appear in court at all. Persons affected by sexual offences are examined in this way, independently of their age. The investigating judge also frequently carries out examinations of children or juveniles with regard to other serious offences. These examinations are recorded on video and can then be used in the subsequent trial instead of conducting another examination.

Investigative proceedings can take a long time. Of course, the persons affected and, in fact, anyone who has filed a criminal complaint, can inquire about the status of the case with the police or the public prosecutor's office. For this purpose, it is important not to lose the case number received after filing a criminal complaint.

Once the police have finished their work, they generally sum up all the investigation results in a report, which is then sent to the public prosecutor's office together with other documents, such as protocols of witness questioning, photographs etc. The public prosecutor in charge then decides on the further course of the proceedings.

Conclusion of the proceedings: Discontinuance or indictment

If, upon concluding the investigation, the public prosecutor’s office does not have enough evidence to support the assumption that the suspect is guilty, it concludes the investigative proceeding by way of discontinuance. Before doing so, of course, it must carefully examine all witness statements and other evidence. If the proceedings are discontinued, the accused person does not bear any consequences.

Likewise, where petty offences are concerned, the public prosecutor's office may discontinue the proceedings if the accused person’s guilt is considered to be minor (section 153 of the Code of Criminal Procedure – Strafprozessordnung - StPO). It may also impose certain conditions on the accused person, such as payment of a sum of money, and then terminate the proceedings when the accused person complies with this condition (section 153a of the Code of Criminal Procedure). In certain cases, the public prosecutor's office may make that decision only with the consent of the court.

If the public prosecutor's office deems the evidence to be sufficient, it files an indictment or, in less serious cases, makes a motion for a penal order to be issued. In both cases it draws up a document describing and demonstrating the offence (indictment). It must state which criminal provisions the accused person has violated and how this can be proven.

The purpose of this is to provide the court with a summary of the material gathered during the investigative proceedings. Accused persons are also provided with a copy of the indictment, so that they know what exactly they are accused of. The public prosecutor's office submits the indictment or the motion for issuance of a penal order to the court.