CSI: Documentation

It’s not sexy and can be tedious, but documentation is the most important aspect of crime scene investigation. Everyone relies on having accurate information about the scene and any evidence (or lack thereof) inside. Oftentimes, lawyers and police officers never see the crime scene itself and just rely on the hopefully extensive documentation of it.

So, how do we document crime scenes?

Cameras
Obviously, one of the biggest assets for a crime scene is the camera. Capturing the scene or evidence means good lighting, using a number, and adding a scale. Too often a tech forgets to include a scale (either a formal paper one or a quarter) and frustrates investigators later.

Maps
Considering the hi-tech gear crime scene investigators have at their disposal, it might be surprising to learn that a big part of documenting a scene involves hand drawn maps. The maps often give a top-down view of the scene to show where everything is in relation to each other, but they don’t always. When something is buried, the maps provide a slice view of the ground and how far down the body or evidence was.

Total Station
I’ve talked in-depth about the Total Station before, but essentially it creates a 3D map of the scene. It’s equally effective indoors and outdoors and—with the right software—lets future investigators virtually ‘walk’ through the crime scene. It’s especially useful when dealing with evidence that can’t be rendered on a 2D map like the height of the blood spatter or the depth of the buried body.

Notes
Anyone can take notes, but often the person in charge is responsible for the official scene notes. These consist of everything from first impressions to how the crime scene is processed, what kind of equipment is used, who is present, when people arrive, the address, temperature, weather conditions, etc. The general advice is ‘when in doubt, write it down.’  You never know what a lawyer or investigator will need to know in the future. Remember, documentation is not analysis.

Video
Sometimes, crime scene investigators shoot video of the scene. This not only documents the scene itself, but also the investigators’ processes. A lot of investigation can damage the scene (think prying up a floorboard, cutting open a mattress, or dusting for fingerprints), so it’s nice to see that the window was already broken when CSI arrived so you know that the glass shards should be considered evidence, whereas the wall was broken open by investigators and shouldn’t be considered part of the crime. It’s also very helpful for homeowners who’ve been the victims of a crime for their insurance companies.

Evidence List
Separate from the notes is the list of evidence and the corresponding numbers. This may seem like extra paperwork, but it’s essential. If you’ve got three bullet holes in a wall, you need to know which number corresponds to the one on the right to match up the pictures with the maps. Even if you don’t have multiple pieces of similar evidence, there may be pictures of something that you can’t tell what it is (that’s usually a sign you need a new camera or photographer) and having a list that quickly identifies #16 as candle wax can save you a lot of headache.