Lab Report- Blood, Penelope Preston Case PDF

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Summary

One of the lab reports that is mandatory for this class...

Description

Case # 2017-420-FILL IN YOUR CASE NUMBER Page 1 of 3

UNH FORENSICS CRIME LAB REPORT Report title

Date report issued

Blood Lab

4/18/18

Examiner name

Examiner signature

Examining laboratory division

Mary O’Hara

Mary O’Hara

Serology

Submitting agency

Items submitted

Durham PD

Blood

Introduction The reason for this investigation being conducted is because Penelope Preston, age 37 of Acme Construction, was murdered on February 14th, 2018, in Rudman Hall. We previously analyzed glass, soil, hair, paint chips, fingerprints, bullets, and shoeprints found at the crime scene, and we are now analyzing blood because some samples were found at the crime scene as well. The question we are asking here is “Who murdered Penelope?”. The blood samples that were collected from the crime scene by our CSI unit was compared with the samples that were collected from suspects interviewed at the police station for questioning late last week. Suspected blood from a handprint, bandage, and a hammer are being examined and compared to all of the current suspect’s blood, as well as the victim’s blood. My running hypothesis is that Tommy, Aaron Nancy, and John worked together as a team to murder Penelope because John had the closest match out of all the suspects from the soil and grass lab, and Tommy and Aaron had the closest match out of all the suspects from the hair and paint chips lab. Everyone except Aaron had a matching fingerprint on the scene, but he will not be left out of my hypothesis due to his matches in the previous labs. We will be able to test this hypothesis by analyzing whether or not the blood on the three crime scene items is really blood, and if it is we can compare it to the suspect’s blood to see if there are matches. Nancy is now in my running hypothesis because her lipstick matched the sample found on a crime scene bandage in a previous lab. Materials and Methods The first test we did was the presumptive Phenolphthalein (Kastle-Meyer) Test. First, we dabbed a moistened cotton swab with water on to your test item in the area suspected to contain blood, and then we applied the test reagents to this swab and followed the directions that came with the kit. If the swab turned pink, the fluid is presumed to be blood, and we would then do a Hemastix test with it. If not, we would rule out the sample. For the Hemastix test, we wet a sterile swab with water and dabbed it on the same tested items in the first part. Then we dabbed that onto the end of the hemastix and made note if it changed color or not. If it did, then it is a confirmed blood sample. If it didn’t, it is confirmed to not be blood.

This report does not constitute the entire case file.

Case # 2017-420-FILL IN YOUR CASE NUMBER Page 2 of 3 As for the blood typing, we first performed a test on each of the known blood samples Once we tested the knowns, we tested the crime scene blood samples, the reference sample from the victim, and the samples from the suspects. We tested all of these in a separate plastic blood typing slide. To do this, we first placed a drop of the first sample into each well of a plastic blood typing slide and added a drop of the anti-A serum to the well labeled A and did the same for B and Rh. We used a different mixing stick for each well and stirred the sample and antiserum. Then, we determined if agglutination, or clumping has occurred, and repeated this procedure for each known and questioned sample. Results (all a consensus of lab LO3) Phenolphthalein Hemastix A+ CS Handprint Positive Positive CS Bandage Positive Positive CS Hammer Positive Positive John Aaron A+ Tommy ABPenelope O+ Nancy B+ CS Handprint A+ CS Hammer O+

Discussion The purpose of analyzing the crime scene blood samples was to see if they are confirmed as blood, and the blood typing was done to see if any of the suspects or the victim’s blood matched ant of the samples found at the crime scene. The highlighted selections above demonstrate any matches found. For both the Phenolphthalein and the Hemastix test, the handprint, bandage, and hammer found at the crime scene all had confirmatory samples of blood on them. For the blood typing, John and Aaron had A+ blood, Tommy had AB- blood, Penelope had O+ blood, Nancy had B+ blood, the handprint had A+ blood, and the hammer had O+ blood. My new running hypothesis is the same as my previous one, which is that Tommy, Aaron Nancy, and John worked together as a team to murder Penelope because John had the closest match out of all the suspects from the soil and grass lab, and Tommy and Aaron had the closest match out of all the suspects from the hair and paint chips lab. Everyone except Aaron had a matching fingerprint on the scene, but he will not be left out of my hypothesis due to his matches in the previous labs. We will be able to test this hypothesis by analyzing whether or not the blood on the three crime scene items is really blood, and if it is we can compare it to the suspect’s blood to see if there are matches. Nancy is in my running hypothesis because her lipstick matched the sample found on a crime scene bandage in a previous lab. These results from this lab confirm that John or Aaron left the bloody handprint on the crime scene, so I This report does not constitute the entire case file.

Case # 2017-420-FILL IN YOUR CASE NUMBER Page 3 of 3 predict that maybe not all of these suspects played a part in the actual murder, but that it was either John or Aaron that actually carried out the killing of Penelope. Going further, I would like to test drug toxicology present in the victim, as well as the current suspects.

This report does not constitute the entire case file....