How a Private Investigator Might Process a Crime Scene

A criminal defense attorney might ask a private investigator to critique the processing of a crime scene, or a private investigator might conduct her own crime scene processing for a client. You’d be surprised the evidence that can be found days, weeks, even months after law enforcement has closed the crime scene for their investigations.

The basic steps an investigator follows, including law enforcement investigators, typically include the following:

1. Check the condition of any victims and arrange medical treatment if necessary.
2. Secure and protect the crime scene. Keep in mind the possibility this crime scene might be the first in a series of crime scenes.
3. Determine if further search is legal. If yes, the private investigator must obtain consent from the investigating authority or property owner, such as law enforcement or a landlord. If the investigator is a law enforcement officer, he obtains a search warrant from a local judge.
4. Search, sketch, and document. Precise measurements of the crime scene include an accurate sketch containing a key, a scale and a legend noting the day, time, location and weather conditions.  It is also useful to document compass directions on the sketch. Also, if documenting the crime scene via photographs or video, it is useful to film dimensions – height, width and length — with a measuring tape.
5. Document the crime scene and its physical evidence. In law enforcement, a videographer typically accompanies an assigned officer on the initial walk-through of a crime scene. Similarly, a private investigator can document the crime scene layout with photographs or video. It is  important to take close-up photographs of important items of evidence, such as footwear or impressions of objects.
6. Handle the evidence so as to not contaminate it. Such precautions include wearing latex gloves and inserting evidence into plastic baggies.
7. Collect, mark and catalogue evidence.
8. Preserve the evidence in a central, organized location, such as a locked closet. 

Have a good weekend, Writing PIs

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Article is now available in How Do Private Eyes Do That?

 

Answering Writers’ Questions: How Long Does an Area Remain a Crime Scene?

Writer’s Question: Is there a time frame that an area remains a crime scene? I’m picturing the yellow caution tape in a public place and wondering how long that remains up.  What kind of time frame might apply to a crime scene in a residence (for example, if someone is found dead in a family room, how long do the residents of the house need to stay out of the room?) I’m thinking that from the time the police leave to when a PI shows up, a lot could happen in that room if a family member so desires.

Guns, Gams, and Gumshoes’s Answer: A police crime scene excludes all but those who are trained to respect procedures for preservation and collection of evidence.  Generally speaking, after a period of approximately 1-24 hours, the area is returned to normal use.

Regarding a crime scene in a residence, specifically (per your question) a dead body found therein: Be mindful that police will remove those parts of the family room that they consider important evidence (for example, blood-stained carpeting and drywall spattered with blood).  Also, police will photograph/videotape the family room in the exact state in which they found it.  In other words, by the time the family returns and changes anything, the PI will have copies of police photographs as well as access to physical evidence that’s within police custody.  There are certainly instances where PIs would still seek access to the home (for example, to photograph the layout, measurements, etc.) but that is accomplished through court order or consent of the victim’s family.

Writing PIs