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The case presented in this paper concerns an examination that was conducted on a vehicle that had visible stickers on the trunk lid when it was photographed by security cameras near a crime scene and a recovered vehicle that had no stickers on the trunk lid to determine whether they were the same vehicle. By using an alternate light source to examine the locations of the stickers, a forensic expert was able to confirm that the vehicle in question was indeed the same vehicle that was observed in the security camera footage. [ABSTRACT FROM AUTHOR]

Increasingly in courts, the source of forensic DNA trace evidence is not challenged by the defence. Instead, the issue relates to how the suspect's DNA got to the crime scene, suggesting it arrived via a legitimate activity. Many burglaries are committed using a new lock-picking method called 'foil impressioning', which involves inserting aluminium foil into the lock. When DNA is recovered from this foil, suspects will say that they only cut the foil and sell or discard it, to be used later in lock-picking by someone else. This study elucidates the probabilities of recovering DNA profiles from aluminium foil in three situations: (1) when a person only cuts the foil, (2) when they cut and then use it for lock-picking and (3) when they cut it and someone else uses it for lock-picking. Using a Bayesian network, we conclude that the probability of recovering a person's DNA profile from foil inside a picked lock is seven times higher if they picked the lock than if they only cut the foil. This study demonstrates how likelihood ratios based on probabilistic models of DNA transfer and persistence can now help the court address questions about the mode of deposition of DNA traces. [ABSTRACT FROM AUTHOR]

Physical matching methods are a family of well‐known methods that are utilized in order to determine whether two pieces of a tearable/breakable material used to be one object. When performing physical match of polymers, it is sometimes difficult to reach an unambiguous conclusion. This is due to various reasons. One is when the tear/fracture resides in an inaccessible or hidden‐from‐view region of the piece. Another is when the shape of the tear/fracture at the object's tear/fracture line is insufficient for deducing a complete match. Third is deficiency of material along this line. These are examples of processes where the line is affected so drastically, so that a match renders impossible. Specifically, when addressing elastic materials, the tear/fracture line may even be squashed. This may also be a reason for difficulty in performing a physical match. In this paper, a method is proposed where a match is alternatively achieved by means of photographic comparison of marks on the surface topography of the pieces‐in‐question. Comparisons of pairs of torn pieces of silicon rubber were made. The procedure involved photography of the surface topography the pieces. Then, the photographs were horizontally mirror‐flipped. Lastly, a comparison was made between two photographs: a photograph of one piece and a mirror‐flipped photograph of the opposite piece. The results show that after comparing the pieces to one another, only one unique pair turned out to be positively matched. Using the proposed method, not only the comparison is done by a more informative method (comparing to physical match), it is also more convenient, faster, less expensive, and technically simpler. [ABSTRACT FROM AUTHOR]

This paper describes the appearance and effects of a serial number alteration technique. The technique involves thermal treatment of the imprinted area. By locally melting the metal, a liquid metal pool is created in the imprint area that alters the metal's "memory". Existing chemical approaches (e.g., Fry's reagent) to number restoration was ineffective in restoring numbers altered or obliterated by this technique. [ABSTRACT FROM AUTHOR]