On-site investigation is carried out in instances where direct observation is necessary for establishing or clarifying a fact material to criminal proceedings. Search may be carried out by the State Attorney, investigator or police, without the court warrant, when they carry out an on-site investigation of the site where a criminal offence was committed which is subject to public prosecution. Search may be carried out immediately or within eight hours since the criminal offence was discovered. Exceptions are searches of flats or other premises that may be carried out only in accordance with the special law regulating special conditions for the search of those places.
Through observation, the facts in the procedure are determined or clarified by observing with one's own senses and their aids.
When conducting an investigation, data that are important with regard to the meaning of such an action or for determining the identity of certain objects (description, measurements and size of objects or traces, marking of objects, etc.) will be entered in the record, and if sketches were made, drawings, plans, photographs, film or other technical recordings, this will be stated in the minutes and attached to the minutes.
In addition to the investigation of the place where the crime was committed, a reconstruction and an experiment can be carried out, which can be determined for the purpose of verification presented evidence or establishing facts that are important for clarifying the matter. The difference between an experiment and a reconstruction is that the reconstruction is done so that the actions or situations are repeated in the conditions under which they were performed evidence the event took place, while an experiment is undertaken to examine the impact certain circumstances to a certain thing, state or relationship.