Mod 4 - presumptive id fnsc2200 semester 2 period PDF

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Lecture notes on presumptive for the course title mysteries of forensic science. Semester 2 period. Captures a comprehensive topic on the course....

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MOD 4 – PRESUMPTIVE IDENTIFICATION Learning Objectives ä Understand the different levels of identification ä Describe the various evidence which contribute to victim identification ä Explain the process by which a personal identification is made Why identify? Identification of a deceased individual is usually one of the first tasks in a forensic investigation. Why do we need to identify a person? 1. Crime Scene: an investigation into a criminal death cannot begin until the deceased has been positively identified (offender/victim; premeditation; missing accounted for?) 2. Legal (assets, marriage, dependents, work, burial) 3. Moral (friends & relatives, social, closure)

Legal boundaries Cause of death  Medical determination  Any condition that leads or contributes to death e.g., cancer, heart attack, gunshot wound, drowning...  Can become complicated when many factors involved

 Decided by a pathologist Manner of death  Legal determination  Based on evidence and opinion – usually decided by the coroner  Natural – Accidental – Suicidal – Homicidal – Undetermined

Who decides? ä The coroner makes a legal determination as to the manner of death and identification ä The pathologist provides a legal opinion about the cause of death ä The anthropologist contributes an opinion about skeletal remains

Anthropologist vs Pathologist Forensic Anthropologist  Usually deal with skeletonised remains  Information from hard tissues  May be partially fleshed and often fragmented

Towards personal identification Presumptive  An individual fits the biological profile of the skeletal remains  Any number of individuals may fit the same biological profile  Tentative ID – clothing, possessions, location of body

Mass Disaster Identification Identification is not a priority when:

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Forensic Pathologist  Typically examines a fleshed body  Information from soft tissues  Medically qualified

Positive  Results from information exclusive to only one individual  Fingerprints, dental radiographs, prostheses and unique anomalies  DNA  Most reliable: fingerprint matching  Legal requirement

MOD 4 – PRESUMPTIVE IDENTIFICATION ä Resources are limited ä Identification is not the mandate Disaster: Unexpected event causing death or injuring to many people ä traffic accidents, ä natural disasters, ä technical accidents (fires, explosions), ä terrorist attacks and events occurring within the context of wars. It is important to distinguish between open and closed forms of disaster. ä Closed: the names of deceased known ä Open: the number of affected people is unknown

Interpol (International Criminal Police Organization) ä Many countries, including Australia, use the identification booklet produced by Interpol for identification in mass disasters. For each body there are two booklets divided into a number of sections: Yellow (antemortem)

Pink (postmortem)

W: personal data of the missing person B: report on the recovery of the body from the site C: personal belongings C: personal belongings D: physical characteristics D: physical characteristics E: medical information E: medical information F: dental information F: dental information G: any other information G: any other information Identification Procedure ä Yellow Interpol ante-mortem form compared to pink postmortem form. ä The yellow forms are first excluded. ä Information from records and x-rays compared to dental examination of the deceased. ä If an identification is made a "Victim Identification Report" is completed. Possible Conclusions 1. Positive ID: antemortem and postmortem information matches 2. Possible: consistent features, need to use additional information 3. Insufficient: evidence to confirm or deny 4. Exclusion: the deceased is not who it was thought to be

Means of Identification  Visual (usual case) Positive (primary) Identification ä DNA ä Fingerprints ä Dentition ä X-ray comparison

Presumptive (secondary) identification ä Personal markers ä Facial superimposition ä Biological profile ä Personal property

Condition of remains that cannot/are hard to be identified

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MOD 4 – PRESUMPTIVE IDENTIFICATION     

Fragmented Water emersion Partially fleshed Burned victims Skeletonised or desiccated remains

Fingerprints Are reliable indicators of identity ä Unique: absolute congruence between the papillary ridges in the fingers of two different individuals or in different fingers of the same persons does not exist. ä Do not change: Papillary ridges are formed in the fourth month of gestation and remain unchanged even beyond death. They grow back in the same pattern following minor injuries. More severe injuries result in permanent scarring. ä Can be classified: Because fingerprints can be categorised, they can be identified and registered systematically and thus subsequently retrieved easily for purposes of comparison.

DNA Identification  Is a proven source of material for identification  Is a significant portion of the genetic information contained in a cell is unique to a specific individual and thus differs from one person to the next (except in identical twins).  Can be performed even on cases involving partial, severely decomposed remains; DNA matching is the best way to identify body parts.  Match can be based on profiles from relatives, self‐samples or belongings.  Analysis can be automated enabling a high quality and high throughput setting.  Prevention of contamination and maintenance of chain of custody is crucial during recovery, storage and analysis.

Dental Identification The unique structures and traits of human teeth and jaws readily lend themselves to use in the identification of living and deceased individuals.  Useful for: 9 recently deceased 9 skeletons 9 incinerated remains  Especially important when visual identification is not possible due to the condition of the remains or absence of someone to do it (friends/relatives)  Cheap and quick compared to DNA which is not always available  Teeth and fillings are very strong and resistant to heat, decomposition and destruction

X-ray comparison Whole body X‐rays (or CT‐scan) used for - Dental examination - Cause of death, skeletal fractures - Antemortem anomalies (ie sinus cavities) and pathologies - Medical procedures, screening for foreign bodies such as pacemakers, implants, etc

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MOD 4 – PRESUMPTIVE IDENTIFICATION Compared with:  Any original antemortem medical or odontological records, charts, treatment records, xrays, and mouth guards

Personal markers A personal description consists of basic data (age, gender, height, ethnic affiliation) and specific peculiarities: - Pacemakers - Prosthetics - Implants - Tattoos

Facial superimposition \ Forensic facial reconstruction is the reproduction of the lost or unknown facial features of an individual, for the purposes of recognition and identification. \ This process involves the overlay of ante-mortem images of the suspect with photographic or video views of the skull in order to compare skeletal and facial features. \ The technique is rapidly improving as more sophisticated electronic equipment is introduced into research. \ Facial recognition can be divided into four categories: 1. Replacing and repositioning damaged or restored soft tissue onto a skull 2. The use of photographic transparencies and drawings in an identikit type system 3. The technique of graphic, photographic or video superimposition 4. Plastic or three-dimensional reconstruction face over a skull using modelling clay  this is an interpretation and not direct comparison

Biological profile (adults)  Age: Visual (i.e. pubic symphysis)  Sex: Metric (i.e. scapula) & Non-metric (i.e. sub-pubic angle)  Stature: Metric (i.e. femoral length)  Ancestry: Metrics (i.e. CRANID, FORDISC) & Visual (i.e. cranial shape)  Other: Musculoskeletal markers

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