Written reports are an integral part of any investigation. They establish a record of pertinent events and observations that serves as the basis for formal inquiries such as criminal investigations and disciplinary proceedings. One of the most effective ways to present information in an investigation report is through use of the narrative style.
Take notes. If you are investigating a crime scene, write down all relevant information that relates to the incident you are investigating. Include as much detail in your notes as possible; you can always pare them down later when finalizing the report. Perform any required field tests and review the reports of everyone else involved with the investigation, such as a coroner, forensic scientist or shift supervisor.
Interview all witnesses or persons associated with the issue at hand. Thoroughly describe all people, events and items involved in the incident being investigated. Ask as many questions as you feel are necessary and take written statements from everyone who has relevant information. Most law enforcement agencies or regulating authorities have forms on which witnesses write their official statements. Obtain the contact information of everyone you question so that you can ask follow-up questions or send subpoenas for hearings.
Organize your information. Create subheadings for your report to help present your information in a logical manner. Typical subheadings for investigative reports include "Background," "Incident Description," "Witness Statements" and "Officer/Agency Action."
Write an account of the incident in chronological order. Use the active voice and avoid pronouns such as "he" or "she" by using proper names whenever possible. This makes your writing clearer. Avoid unnecessary adjectives or embellishment, and do not repeat yourself. Refrain from including your personal feelings or conclusions on the matter. You are not there to decide the outcome of the situation; your purpose is to create a record of what happened.
Proofread your work and check it for factual errors. Errors in an investigative report can have severe consequences for all parties, including the investigator, once an incident reaches the court system.