Establishing the identity of accused persons and other persons in criminal proceedings is as a rule, left to the police. The police may take a photograph, fingerprints and a mouth swab of a person suspected of having committed a crime. They may also publish the photograph of the suspect if its publication is necessary to establish his or her identity or in other instances where it is important for the successful execution of the proceedings. If it is necessary to establish to whom the fingerprints or biological traces found on particular objects belong, the police may take the fingerprints and mouth swabs of persons likely to have come in contact with such objects. An accused is asked to tell the court his or her name, nickname if any, his parents' names, his mother's maiden name, his places of birth and residence, date of birth, personal identification number, nationality, citizenship and occupation. A witness is asked to tell the court his or her name, date of birth, place of residence, occupation, place of employment and possible family relationship with the accused or injured person.