Answer all questions in Section A and one question from Section B.

SECTION A

Consider the evidence presented in cases one and two and then answer all questions associated with each case.

CASE ONE

The body of a dead woman has been discovered lying on the living room floor in her flat and the following observations were made at the scene. The flat was in a squalid and chaotic state. The door to the flat was shut but not locked and there was fresh blood on the inside door handle and throughout the flat. The woman was in her twenties at the time of death, was 1.5 metres tall and weighed 90kg. She was dressed in a thin nightgown. She had several superficial incised wounds to her neck and one deep incised wound that starts under her left ear and travels down towards her larynx. Initial investigations suggest this deep wound may be the cause of death. In addition, she had several superficial incised wounds to her left forearm that were at various stages of healing and recent fingerpad bruising on her upper arms. There was no suicide note.

Question 1.1: From the information provided above, critically appraise the arguments for and against the woman having committed suicide.

Question 1.2: Giving your reasons, explain what further information (evidence) you would require to help you come to a firm decision whether it is a case of suicide or homicide.

CASE TWO

The body of a man has been discovered in a field and the following records were made:

Date of discovery: July 10th

Time of discovery: 9am

Time of sampling entomological evidence: 11am

Numerous adult blowflies of species A and B were flying around, mating and laying eggs in the man’s wounds, mouth and eyes. Eggs, and first instar larvae of species B were found at the site of one of the head wounds and four larvae belonging to species A were also found here – these had just moulted to their second instar.

Life-history data for species A and B

All data represent average minimum duration in days of developmental stages.

Rearing temperature was a constant 22oC.

The base temperature for both species is 2oC

Egg L1 L2 L3 Prepupa Pupa
Species A 1.04 0.98 2.00 11.46 6.54 31.25
Species B 1.07 1.03 2.11 12.08 7.71 33.33

 

Climate Records

Average daily temperatures (oC)

June 4th – June 19th : 13
June 20th – June 28th : 13
June 29th –June 30th : 14
July 1st –July 5th : 16
July 6th : 15
July 7th : 15
July 8th : 16
July 9th : 16
July 10th : 15

 

Question 2.1: Solely on the entomological evidence, calculate when the man died.

SECTION B

Answer one essay question.

  • Evaluate the strengths and limitations of the morphological and physiological changes that take place after death as a means of determining the minimum time since death.
  • Critically discuss how the study of microbial ecology can be used in one or several different aspects of the forensic sciences.
  • With reference to examples, discuss the advantages and limitations of using diatoms to diagnose death by drowning.