CSI Laboratory Analysis

Case Study: Redcott Cottage

The presence of the two glasses of gin and tonic on the drinks table in the lounge indicates the possibility of two people being inside the house at the moment of the attack. Performing the cyanoacrylate fuming method, the fingerprints on the glasses will become visible and so they could be collected and further compared to the police records in order to identify the people located inside the house around the time of the attack. Moreover, there might be traces of saliva left on the margins of the glasses which can be identified using the RSID test and then further analyzed for matching the DNA using the STR/Y-STR method.

The CSI Laboratory Analysis showed that the blood recovered from around the body and the blood recovered from the drinks table belong to the same blood group – . A deeper analysis of the blood samples needs to be carried out in order to identify and compare the DNA contained by each one of them. I expect the result of this test to show that the DNA from the samples do not match, therefore indicating that there were indeed two people inside the house at the moment of the attack, which would be consistent with the direction of the pellets shot and would also explain the trail of blood left from the drinks table to the back door and outside.

The Cobalt Thiocyanate test applied on the white powder identified at the crime scene returned a positive result for cocaine. However, it is known that other compounds such as Diphenhydramine and Lidocaine, known as false positives for cocaine, also give blue organic layers under this test. Therefore, the substance should be analyzed in more depth using the GC-MS method. Moreover, the stomach content of the victim as well as his blood should be tested in order to determine if the victim was under the influence of any substances before he was killed.

The evidence show that there were two attackers. The first attacker approached the house from the east side and started shooting through the lounge window, with a shotgun using Winchester Super Double X Magnum pellets, targeting the person who was seated at the table. The fact that more than one shotgun cartridge wadding were found directly underneath the window and inside the piano shows that the attacker fired at least twice, one of the shots being obstructed by the piano, thus explaining the glass shards and pellets found imbedded in its body work. Some of the pellets reached the drinks table and also the person standing next to it, who was injured, started bleeding, and most probably fell to the ground.

The attacker then went to the front door and broke into the house by forcing the entry. Using the cyanoacrylate fuming method any potential fingerprints on the door handle and on the area surrounding it will be revealed.

The second attacker approached the house from the north side, positioning himself in front of the kitchen window and targeting the person who was located in doorway between the kitchen and lounge. He fired at least twice, with a shotgun using Remington Premier HEVISHOT pellets. One of the shots hit the man in his upper left arm, causing his death, and the others hit the wall south of the door and the doorframe.

The hypostasis being mostly on the front aspect of the body shows that the victim was lying face down. Moreover, having his head pointing towards east and legs towards west indicates that the man was facing the lounge when he was shot dead. Hence, considering the trajectory of the pellets, the places where they were found and the fact that the victim was shot only on his left side, we can conclude that the attacker was situated on the left hand side of the subject, briefly behind him, position that supports the hypothesis of the intruder shooting from outside the house through the kitchen window.

By using optical methods and specific chemical tests (AAS/NAA) on the victim’s body, particularly around the wounds, we would get information about the presence, the quantity and the pattern of the gun shot residue, thus being able to evaluate the firing distance. In this case I expect the tests to show that the gun was fired at an intermediate range, approximately a few meters. This result would also be consistent with the external aspect of the victim’s wounds such as the diameter of the shot pattern, the area of superficial abrasion, the dimensions of the exit and re-entry wounds and the lack of stippling or fouling marks surrounding the entry wounds.

It is important to understand the composition of the trail of footprints which starts from the doorway between the kitchen and lounge and leads to the front door in order to identify the access route of the first attacker. Using Luminol, we can establish if the footprints were made in blood. If this test returns a negative result, we can further use mass spectroscopy to identify the composition of the footprints and compare them with soil samples from outside the house. If the test correlates the two samples, and knowing that the footprints start only from the kitchen door, the conclusion that the attacker entered the house through the kitchen window may be drawn. Moreover, the work surface and sink situated below the kitchen window should be carefully inspected for footprints or any other signs, such as fingerprints, fibres, hair, blood that might indicate the window to be the attacker’s access way to the house and lead in any way to his identification.

After the attack, both intruders left the house through the front door, hypothesis furtherly supported by the trail of footprints seen exiting through the front door. Later, the person injured raised from the ground and left the house through the back door, thus leaving the trail of blood found at the crime scene on his path.