A preliminary investigation is the initial response to a report that a crime has occurred. It is the first investigative effort undertaken by a member of the police department. The primary objective of the preliminary investigation is to determine who committed the crime and to apprehend the offender. The investigation collects evidence that supports that a crime has occurred, the identification of the offender, and the arrest and subsequent conviction of the offender. The framework of the preliminary investigation is based on the following major tasks:
- Verification that an offense has occurred
- Identification of the victim, the place of the crime, and the time of the crime
- Identification of solvability factors
- Communication of the circumstances of the crime
- Identification of those investigative tasks completed and those yet to be done
The officer conducting the preliminary investigation is responsible for performing basic roles such as assessing and ensuring scene safety, determining if any additional resources are needed, advising the dispatcher and other responding units of on-scene conditions, providing necessary medical interventions, and requesting emergency services. During the preliminary investigation, the police investigate what has happened and what damages have occurred to the victims of the crime. The police will question the victim of the crime, the suspect, and any witnesses, as well as collect evidence such as statements, photos, and carry out technical investigations. The information gathered during the preliminary investigation will be used to determine whether a more thorough investigation is necessary. In some cases, the preliminary investigation may be enough to lead to an arrest and charges being filed. One of the primary benefits of a preliminary investigation is that it helps to preserve the integrity of the crime scene. By securing the area and gathering evidence early on, law enforcement officers can help to ensure that important information is not lost or contaminated.
