Shoe-Printing

Shoe-prints:Examiners use several methods for collecting footwear, but it depends on the type of impression found. For impressions in soil, snow or other soft surfaces, they will use casting which is a common use one. For imprints, examiners try to collect the entire object containing the imprint, such as a whole sheet of paper or cardboard with a shoe print. When not possible, the examiner would use a lifting technique to transfer the imprint to a medium that can be sent to a laboratory. While taking pictures, we should the flash and hold it at an angle for side-lighting. Once the imprint was lifted or casted, we would put the evidence in a paper back and ship it to a forensics lab which would help determine the brand of the shoe and the size of the shoe. Shoe-prints must be properly documented, collected and preserved in order to maintain the integrity of the evidence. Impression evidence can be easily damaged, so steps must be taken to avoid damage to the evidence.
-http://www.crime-scene-investigator.net/ SimplifiedGuideFootwearTireTracks.pdf …show more content…
In order to collect the white powder, we would put it in a hard-case such as a pill-box or plastic vile so that moisture does not get to the substance like it would if it were stored in a plastic bag. For Presumptive testing, we would use a spot test where we would put Cobalt Thiocynate on some of the white powder substance in order to determine if the substance happens to be cocaine or not. If the substance turns blue, then it is evident that the white powder is cocaine because of the chemical reaction of the two chemicals. For Confirmatory testing, we would use the solution of cobalt Thiocynate and white powder that turned blue and add hydrochloric acid. If the substance that turned blue ends up turning pink, then we can confirm that the white powder is definitely