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Even though they are the most common, they are also the most easily contaminated and therefore, must be handled literally with kid gloves. When a crime scene investigator is called upon to collect hair sample evidence, he can do this a number of ways. However, the most common method is to ; “use the fingers or tweezers to pick up hair, place in paper bundles or coin envelopes which should then be folded and sealed in larger envelopes. Label the outer sealed envelope.” In instances when the hair is found to be mixed with blood or other items at the crime scene, it is important to preserve all the types of evidence present.
Therefore, in order to collect the hair sample while attached to say, a bloodstain, a CSI might find himself leaving the hair intact where it dried up or got mixed up in because of the method by which it is recovered and packed ; “If the object is small, mark it, wrap it, and seal it in an envelope. If the object is large, wrap the area containing the hair in paper to prevent loss of hairs during shipment. “ (“”Evidence Collection Guidelines”) Tests that can be performed on a hair sample include Fresh Blood on the other hand, “.
needs to be absorbed in a gauze pad or sterile cloth and allowed to dry thoroughly”. If whole pieces of clothing are retrieved, “label and roll in paper or place in a brown paper bag or box and seal and label container. Place only one item in each container. Do not use plastic containers., then allow it to dry at room temperature at the crime lab.” (“”Evidence Collection Guidelines”) These types of evidence cannot be exposed to sunlight as it will contaminate the blood. Dried blood on the other hand, requires that the clothing be wrapped in clean containers in the same manner as fresh blood.
If the blood is found on small objects, the object should be wrapped, labeled, and sealed in a box before being shipped to the laboratory. (“”Evidence Collection Guidelines”). It is important to not mix blood stains and instead place any stains retrieved from table or counter tops in separate envelopes. It is important to not retrieve the blood evidence with moistened cloth or tissue paper because its chemical composition will influence the freshly recovered evidence. One of the tests can be performed on both dry and liquid samples would be DNA matching and blood chemical analysis for those suspected of being poisoned.
When recovering firearms, it is important to wear latex gloves in order to preserve any DNA, trace, or fingerprints on the gun. Remember to treat it as a loaded gun even though the visual evidence indicates the cartridge is empty. Remember that there may be unfired bullets in the chamber and therefore, the weapon should not be shipped by any method for safety reasons. Prior to sending the gun to the lab, it is of the utmost importance that the serial number, make and model, caliber and model markings are properly recorded because “Marking firearms is important since duplicate serial numbers are sometimes found on different guns of the same make and general type.
” (“”Evidence Collection Guidelines”) When a gun is recovered at the crime scene, shell casings from the bullets won't be far behind. As with the gun itself, latex gloves are the order of the day when recovering the bullet casings. The bullets should be wrapped in paper or dropped into the small evidence bag that are properly labeled. Once a while, labeled pill boxes and envelopes may
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