This is a picture of me lifting prints off of a glass plate. We had to place a print on glass and try to remove it by using fingerprint powder and a sticky plastic to get a clear print. This reminds me of how we were taught to lift the prints correctly and the activities that went along with it.
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What are fingerprints? A fingerprint is an impression or mark made on a surface by a person's fingertip, especially as used for identifying individuals from the unique pattern of whorls and lines. There are 3 types of prints that can be found at a crime scene. A visible print is one that is clearly shown due to being in contact with blood or paint and then makes contact with something else leaving a visible print. A latent print is the most commonly found print at crime scenes. They are known to be barely visible to the naked eye and can be lifted using a power and special clear “sticker”. And lastly plastic prints are prints impressed into a material like mud, or concrete, or silly putty.
How are fingerprints classified? Fingerprints are classified by 8 different types of patterns. They can be identified by a national database of fingerprints from all over, it is a good starting point for anytime fingerprints are found. The 8 classifications of fingerprints are: plain arches, tented arches, radial and ulnar loops, plain whorl, central pocket, double loop, and accidental. Everyone’s fingerprints are different and that makes it easier to identify individuals.
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Why are fingerprints valuable as forensic evidence? Fingerprints can be identified as individual evidence because they can be linked to a specific person because everyone has their own fingerprint, no two are alike. In order to identify someone’s fingerprints you need to be able to identify the type of fingerprint it is and what characteristics each print shows. In order to get a clear print investigators use a very fine powder to make the latent(not visible to the human eye) visible. They then use a special sticker to lift the print which should come over very clean and visable.
Reflection: At the beginning of the unit I wasn't really aware of how to identify a fingerprint or what kinds there were and what parts there are on fingerprints such as dot, cicatrix, and abrupt endings. At the end of the unit I was much more informed in the whole aspect of fingerprints and was more knowledgeable. I learned a lot during this unit and I found it interesting to do fingerprinting on the cards and on glass and have to powder them to make them visible and remove them.