A preliminary investigation is a process that takes place immediately after a crime has been committed, in which police or investigators determine whether there is sufficient evidence or cause to charge the defendant or suspect.
The first law enforcement on the scene are usually the ones to carry out any preliminary procedures and help to ensure the safety of law enforcement and citizens. The preliminary investigation often involves steps such as assessing the situation or resolving crime in progress. Afterwards, law enforcement determine if any additional services, such as medical or emergency assistance, are required. According to Legal Source, officers must then determine if a crime has been committed, and if so, what type of crime. Identifying suspects, witnesses and victims can assist officers in determining whether a crime has occurred.
After gathering evidence from the scene, officers must then determine if there is sufficient evidence or reason to arrest and charge any suspects. Officers often use eye-witness accounts, security device footage such as security camera videos or audio, and crime-scene evidence in order to identify and charge any suspected individuals. If there proves to be enough evidence to support a charge, law enforcement may arrest and charge the suspect, who then goes on trial.