A detective is responsible for collecting evidence from a crime scene and analyzing the information he gathers about the crime. He also is responsible for interrogating subjects to try and get a confession. To do his job, a detective needs tools. These range from standard collection tools like gloves and bags to forensic equipment for conducting field drug tests and taking fingerprints. The responsibilities of a detective vary based on the size of the department. In a small department, the detective may be responsible for a variety of tasks.

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A detective is responsible for interviewing suspects and keeping track of evidence in the case.

Recording Equipment

One major responsibility for detectives is questioning witnesses and suspects. To ensure that you are recording all the evidence people are giving you need the proper recording equipment. If a detective is questioning a subject at a police station, a digital or video camera and a recording device are often set up in the room from a vantage point that allows the subject to be observed and heard giving their statement during questioning. The recording device or video camera also is used to capture what the person being interviewed is saying or how he is reacting to the line of questioning. For investigations that take place in the field, a hand-held recording device is used, especially when interrogating witnesses.

Standard Evidence Kit

A standard evidence kit is required of all detectives. These kits include gloves, envelopes and/or plastic bags to collect evidence without contaminating it. Other items in this kit may include swab kits for collecting biological evidence and testing equipment to determine what type of biological evidence it is. A general evidence kit contains rudimentary items like tape measures, flashlights and scissors.

Computer

A laptop and/or personal computer are two of the most important tools of a detective. Much of their work involves writing up statements by witnesses and suspects, and then writing up reports for superiors and team members. He is also responsible for taking charge of all the information related to the case, which means that he needs some way to keep track of the information. He can do this with computerized, individualized file folders. He also needs to be able to write up search warrants and submit them to a judge.

Fingerprint

The fingerprint kit helps detectives find and rule out suspects. It helps detectives retrieve fingerprints from the scene of the crime, and allows fingerprints of the victim to be taken, particularly in the case of unidentified cadavers. This kit usually contains fingerprint powder, which sticks to the ridges of a person's palm, feet or fingers. The kit also has adhesive tape to retrieve the fingerprint.