Detecting blood at a crime scene is often essential for determining if a crime did indeed occur and how the act unfolded—crime scene reconstruction. At the scene, a meticulous search for blood can be tedious, time-consuming, and eat up many man-hours.
Shed blood is not always obvious. The stains are not always patent (visible) but rather latent (invisible). The standard in such situations has been to employ Luminol, which can find even very small latent bloodstains. But Luminol takes time and requires darkness—not always obtainable, particularly in outdoor, daytime crime scenes.
A new technology developed by Dr. Meez Islam and colleagues at Teeside University promises to not only be able to detect latent blood spatters quickly but also age the blood very accurately. With month-old stains the device, which uses hyperspectral imaging, can narrow its deposition down to a day and with fresh blood down to an hour. This should greatly help with Time of Death determination—-or at least the time when the blood was shed.
Blood exits the body bright red but with time and oxidation becomes rusty brown and does so along a predictable timeline. Accurate determination of the bloodstain’s color with hyperspectral imaging reveals its approximate age.
Very cool. And potentially very useful.