Whether you are a detective, patrolman, loss-prevention officer, security officer or a private investigator, investigation makes up one of the key duties in your job description. Investigators use a variety of techniques to help solve crimes, uncover information or locate lost people. Learning the skills necessary to become a good investigator takes time and, in some cases, advanced education in a legal field, as well as an understanding of laws pertaining to legal investigation.
Laws Regarding Investigation
Understand the laws of the state or country in which you work---especially if you are a private investigator. Law enforcement officers need to adhere to laws that oversee such investigative techniques as search, seizure and detaining a suspect; these laws vary from state to state and country to country.
Field Investigative Techniques
Learn the fundamentals of interview/interrogation and search---two of the most important field investigative techniques. Interview suspects and witnesses effectively in order to uncover crucial information. Searching, whether property or people, will often lead to items you can use to arrest and convict.
Nonintrusive Investigative Techniques
Familiarize yourself with surveillance and Internet searches--- two investigative techniques considered nonintrusive. Use these low-key techniques to gather information before bringing more aggressive techniques into play---especially in long-term cases where subject history and observation of subject behaviors play a crucial role in an investigation.