Other than examining the dental aspects provided as evidence, what other ways can the victims be identified?
Face Reconstruction
There are two methods of forensic art to reveal a facial likeness of unidentified human using the skull, which are the two-dimensional and three-dimensional facial reconstruction. Facial reconstruction often helps in image building for the investigators in identifying the victims when there are only remnants of the skeleton found. In facial reconstruction, a cleaned skull will be used to construct a digital 3D model of the skull. Tissue depth markers pertaining to the unknown individual’s sex and ancestry are glued onto anatomical facial points of the skull to determine an average shape for that particular face. Artificial eyes are placed in the eye sockets and clay will be applied on the skull following the skull’s contours. Various measurements like the nose thickness, mouth width and eye placement are made and logged. Sometimes props such as spectacles and wig are use on the reconstructed model to better accentuate the features of the individual. . Upon completion, the sculpture is photographed
Referring to the case discussed, the skull found can be used for face reconstruction. The reconstructed model can help to determine if the victims are one of the missing person when compared to the pictures of the missing person. This indirectly helps to identify the victim.
Please refer to this video for a better understanding as this video has clearly shown the procedures on face reconstruction.
Forensic Entomologist
These experts can estimate work out the approximate time of death by analysing the insects that are feeding on a body because different stages of decomposition of the body attracts different kinds of organisms to feed off the body. Besides, the entomologist have to take into considerate about the weather conditions, humidity and temperature, if the body has been buried or are exposed to the elements, body size and weight, clothing, as all these will either increase or decrease the rate of decomposition of the body. The estimated time of the victim’s death can be used to see if it matches with the list of people who are reported missing around that particular time.
Forensic Anthropologists
These experts can estimate work out the approximate time of death by analysing the insects that are feeding on a body because different stages of decomposition of the body attracts different kinds of organisms to feed off the body. Besides, the entomologist have to take into considerate about the weather conditions, humidity and temperature, if the body has been buried or are exposed to the elements, body size and weight, clothing, as all these will either increase or decrease the rate of decomposition of the body. The estimated time of the victim’s death can be used to see if it matches with the list of people who are reported missing around that particular time.
Forensic Anthropologists
By examining skeletal remains, a large amount of information can be derived by these experts. Information like age, sex, stature, special characteristics of a human can be revealed through the 206 bones in an adult human.
We can identify the sex of the skeletal remains by looking at its pelvis bone and size of the skull, adult males tend to have narrower pelvises and a larger skull .Age can be estimated by the degree of the bone growth, eruption of the tooth, calcium and mineral deposits in the bones. Our "bones" are mostly soft cartilage at birth. The cartilage is replaced by hard bone at different centers of growth as we grow. In infants, there are over 300 centers of bone growth which fuse to form the 206 bones in the adult body. Since the centres grow and fuse at known rates, anthropologists can use the pattern to estimate age in children and subadults. Besides, the shape of the skull can also tell if its racial, whether its a Negroid, Caucasoid or Mongoloid heritage. The forensic anthropologists can identify special characteristics such as past injuries or fractured by examining the bones.
All the information found from a skeletal remains can be used to compare with the characteristics of each of the reported missing victim. The victim can be identified if the characteristics such as sex, age, past medical history and so on, met the information found from the skeletal remains.
Figure 1 : Developmental stage differences between (from left to right) 6 months, 6 years, and 8 years of age
Figure 2: Developmental changes to the pubic symphysis, from younger (on left) to older (on right).
Fingerprinting
Fingerprinting
Fingerprints are an individual characteristics, nobody shares the exact same fingerprint pattern, including identical twins. It will remain unchanged for life of an individual unless the prints are changed by permanents cuts or scars. Fingerprints obtained are then processed through the Integrated Automated Fingerprint Identification System (used to find possible matches with fingerprints in the database). If the fingerprint matches with the fingerprints found in the database, the victim can be identified.
Figure 3 and 4 shows different patterns of fingerprints and ridges.
Figure 3
Methods of Fingerprint Detection:
· Argon Ion Lasers –fluorescence techniques for enhancement of chemically developed latent fingerprints
· Ninhydrin- chemical that bonds with the amino acids in fingerprints and will produce a blue or purple color. It works well on paper or cardboard surfaces.
· Cyanoacrylate fuming method (super glue method)- a procedure that is used to develop fingerprints on a variety of objects
· Magnetic powder – use to reveal latent prints and works on shiny surfaces or plastic baggies or containers.
Nuclear DNA Testing
DNA testing is one of the best methods to identify a victim or victims. For identification purpose, it is necessary to collect DNA samples from family members and from personal items or prior medical specimens to compare with the DNA from victim’s remain.
Figure 5: DNA sources(that helps to identify the victims) with different degree of usefulness.
DNA can be collected from very small amounts of blood, mouth (cheek) scrapings, hair roots, urine, semen from the body.
Nuclear DNA- Comes from the cell nucleus, is inherited by both parents. Each person’s DNA is unique except for identical twins. Can be easily damaged by heat or other conditions, hence not always available for to be used for identification. When a sufficient nuclear DNA profile from the victim’s remains matches the nuclear DNA profile from a sample known to have come from the victim, we can be very sure of the identity of the victim.
The mitochondria DNA testing
The majority of our DNA is inherited by both of our parents, which is a complete mixture of our entire ancestor. But there are two pieces of DNA which is inherited in a very simple way. One of these is the mitochondria DNA, which is pass down just through the female line, from mother to daughter and daughter down through the generation so everyone of us would have the same mitochondria DNA as our mothers, and that give us a fantastic opportunity to trace the direct relationship of a victim and to confirm the identity of a victim if there is a female direct relation of the victim. This method was used by the University of Leicester in identifying the skeleton of Richard III, the last Plantagenet King of England, where the skeleton was discovered in a council carpark in Leicester in September 2012. They isolated the mitochondrial DNA taken from the skeleton to do a test. Richard III would have had the same mitochondrial DNA as his sister Anne of York (they would have got it from their mother Cecily Neville). The University then looked for an unbroken mother daughter line from Anne of York to the present day. The University of Leicester page on Richard III confirms that they found two unbroken mother-daughter lines from Anne of York. One of the present day descendants, Michael Ibsen and his siblings all agreed to have their DNA sampled. The other present day descendant also agreed to have their DNA sampled, but they wanted to remain anonymous to the public. The DNA of the anonymous sampler matched both that of Michael Ibsen, and that of the skeleton of Richard III, which proves that they are all descended from Cecily Neville. Similarly in this case, the mitochondrial DNA can be isolated and tested with the list of missing adults and children’s female direct relation. By this, we can actually identify the victims.
Figure 8 : Nuclear DNA and Mitochondrial DNA
Hair Analysis
Hairs are composed primarily of the protein keratin. Age of an individual cannot be determined through the hair by a microscopic examinations because the microscopic appearance of certain human hairs, such as those of infants and elderly individuals, may provide a general indication of age. Besides, some elderly still have “baby hair” on them, so it is unlikely to estimate it is an adult or infant. However, the sex of an individual can be estimated by a microscopic examinations, provided the hair is forcibly removed causing the hair follicle still attaching to it. Sex of the individual can then be estimated through the staining of sex chromatin in the cells found in the follicular tissue.
Each species of animal possesses hair with characteristic length, colour, shape, root appearance, and internal microscopic features that distinguish one animal from another. Same goes to different races of human. The race of the individual can be estimated. Negroid(African) mostly have curly or kinky hair with flattened cross section, larger pigment granules are found compared to Caucasian and Mongoloid hair, and are groups in clumps with different shapes and sizes. Caucasoid (European) mostly have straight or wavy hair and exhibit colours ranging from blonde to brown to black. They have hair shafts which vary from round to oval in cross section and have evenly distributed medium sized pigment granules. As for Mongoloid(Asian), their hair are usually coarse, straight and circular in cross section with a wider diameter than the hairs of the Negroid and Caucasian. Their cuticle(outer layer of hair) is significantly thicker than the other racial groups’ hairs. The medulla (central canal) is continuous and wide also.
In a nut shell, by using a strand of hair found in the crime scene, the sex and also the race of victim can be identified. If DNA is extracted from the follicle cells’ nucleus (if found), it can be searched in the database if there’s any similar DNA, then the victim can be identified.
Figure 7: Forcibly removed hair may have tissue attached to it
Forensic Botany
Forensic botanists look to plant life in order to gain information regarding possible crimes. Leaves, seeds and pollen found either on a body or at the scene of a crime can offer valuable information regarding the timescales of a crime and also if the body has been moved between two or more different locations. Besides, it incorporates several sub disciplines such as dendrochronology (the study of tree rings), systematics (the classification of plants), ecology and forensic palynology (the study of pollen). These can produce specific findings of location of death, decomposition and time of year.
http://www.sfu.museum/forensics/trim/s/videos/bo_role_forensic_botanist-en-VMC3_Flash_Gamma.mov
Blood Stain Analysis
The examination of the shapes, locations and distributions patterns of bloodstains in order to provide and interpretation of the physical events by which they were created that is based on the premise that all bloodstains patterns are characteristic of the forces that have created them.
The blood stain can be analysed through chemical and physical considerations. Upon exiting the body, bloodstains transit from bright red to dark brown, which is attributed to oxidation of oxy-haemoglobin (HbO2) to methaemoglobin (met-Hb) and hemichrome (HC). The fractions of HbO2, met-Hb and HC in a bloodstain can used for age determination of bloodstains and can be measured by Reflectance Spectroscopy. Once blood has left the body it behaves as fluid, gravity acts on the blood, given the right circumstances blood can act according to ballistic theory. Viscosity and surface tension of the blood can also help to determine how it behaves and lead to recreation of crime.
These are the general categories of bloodstains :
Blood spatters can indicate important information such as:
Impression Evidence
Impressions are used to find legitimate matches and the practice works the same way as fingerprinting. There are three main types: Footprints (or shoe impressions), Tire tread impressions and Tool markings.
Impressions are left on hard surface by creating electrostatic charges. Simply sprinkling fingerprint dusting powder over recent footprints will attract powder to the charge and create visual image. However, residual static charges don’t last very long and can be easily upset so forensic experts rely more on the deformation of surface areas. Shoe impressions on materials such as soil, sand or snow can produce a largely three-dimensional footprint. While stains and other residue will leave two-dimensional marks and create a recognizable image. Tire marks are much easier to identify. Defects and wear on a tire tread caused by nails, gravel, and patches can identify a unique set of tires. Lastly, tool marks are created when a tool comes into contact with another object or surface and leaves a significant impression.
Forensic Odontology
Tooth identification
The teeth remain long after all other parts have decayed is because the tooth enamel is harder than any other substance in the human body. Enamel can withstand temperatures of more than 2000 degrees Fahrenheit. Teeth are fragile and may shrink especially through intense heat, but they can be preserved with lacquer and used for identification. Dental work (partial od gold crown) will be distorted by fire but still can aid in identification.
Bite Mark Analysis
Bite marks can be detected on the victim or the perpetrator, or on foodstuffs found at the scene of the crime, when the marks were compared to dental impressions taken. The first step in analyzing the bite is to identify it as human as animal teeth are very different. Then, forensic dentists will take measurements of each individual bite mark and record it. Bite photography must be conducted precisely, to accurately depict the orientation, depth and size of the bite. The bite marks on deceased victims are cut out from the skin and preserved in formalin. Forensic dentists then make a silicone cast of the bite mark. The movement of a person’s jaw and tougue when he or she bites contributes to the type of mark that is left. It is not typical to find bite marks with both upper and lower teeth. Forensic dentists use several different terms to describe the type of bite mark:
Abrasion - a scrape on the skinArtifact - when a piece of the body, such as an ear lobe, is removed through biting
Avulsion - a bite resulting in the removal of skin
Contusion - a bruise
Hemorrhage - a profusely bleeding bite
Incision - a clean, neat wound
Laceration - a puncture wound
The bite mark evidence
Figure 4
Methods of Fingerprint Detection:
· Argon Ion Lasers –fluorescence techniques for enhancement of chemically developed latent fingerprints
· Ninhydrin- chemical that bonds with the amino acids in fingerprints and will produce a blue or purple color. It works well on paper or cardboard surfaces.
· Cyanoacrylate fuming method (super glue method)- a procedure that is used to develop fingerprints on a variety of objects
· Magnetic powder – use to reveal latent prints and works on shiny surfaces or plastic baggies or containers.
Nuclear DNA Testing
DNA testing is one of the best methods to identify a victim or victims. For identification purpose, it is necessary to collect DNA samples from family members and from personal items or prior medical specimens to compare with the DNA from victim’s remain.
Figure 5: DNA sources(that helps to identify the victims) with different degree of usefulness.
DNA can be collected from very small amounts of blood, mouth (cheek) scrapings, hair roots, urine, semen from the body.
Nuclear DNA- Comes from the cell nucleus, is inherited by both parents. Each person’s DNA is unique except for identical twins. Can be easily damaged by heat or other conditions, hence not always available for to be used for identification. When a sufficient nuclear DNA profile from the victim’s remains matches the nuclear DNA profile from a sample known to have come from the victim, we can be very sure of the identity of the victim.
The mitochondria DNA testing
The majority of our DNA is inherited by both of our parents, which is a complete mixture of our entire ancestor. But there are two pieces of DNA which is inherited in a very simple way. One of these is the mitochondria DNA, which is pass down just through the female line, from mother to daughter and daughter down through the generation so everyone of us would have the same mitochondria DNA as our mothers, and that give us a fantastic opportunity to trace the direct relationship of a victim and to confirm the identity of a victim if there is a female direct relation of the victim. This method was used by the University of Leicester in identifying the skeleton of Richard III, the last Plantagenet King of England, where the skeleton was discovered in a council carpark in Leicester in September 2012. They isolated the mitochondrial DNA taken from the skeleton to do a test. Richard III would have had the same mitochondrial DNA as his sister Anne of York (they would have got it from their mother Cecily Neville). The University then looked for an unbroken mother daughter line from Anne of York to the present day. The University of Leicester page on Richard III confirms that they found two unbroken mother-daughter lines from Anne of York. One of the present day descendants, Michael Ibsen and his siblings all agreed to have their DNA sampled. The other present day descendant also agreed to have their DNA sampled, but they wanted to remain anonymous to the public. The DNA of the anonymous sampler matched both that of Michael Ibsen, and that of the skeleton of Richard III, which proves that they are all descended from Cecily Neville. Similarly in this case, the mitochondrial DNA can be isolated and tested with the list of missing adults and children’s female direct relation. By this, we can actually identify the victims.
Figure 8 : Nuclear DNA and Mitochondrial DNA Hair Analysis
Hairs are composed primarily of the protein keratin. Age of an individual cannot be determined through the hair by a microscopic examinations because the microscopic appearance of certain human hairs, such as those of infants and elderly individuals, may provide a general indication of age. Besides, some elderly still have “baby hair” on them, so it is unlikely to estimate it is an adult or infant. However, the sex of an individual can be estimated by a microscopic examinations, provided the hair is forcibly removed causing the hair follicle still attaching to it. Sex of the individual can then be estimated through the staining of sex chromatin in the cells found in the follicular tissue.
Each species of animal possesses hair with characteristic length, colour, shape, root appearance, and internal microscopic features that distinguish one animal from another. Same goes to different races of human. The race of the individual can be estimated. Negroid(African) mostly have curly or kinky hair with flattened cross section, larger pigment granules are found compared to Caucasian and Mongoloid hair, and are groups in clumps with different shapes and sizes. Caucasoid (European) mostly have straight or wavy hair and exhibit colours ranging from blonde to brown to black. They have hair shafts which vary from round to oval in cross section and have evenly distributed medium sized pigment granules. As for Mongoloid(Asian), their hair are usually coarse, straight and circular in cross section with a wider diameter than the hairs of the Negroid and Caucasian. Their cuticle(outer layer of hair) is significantly thicker than the other racial groups’ hairs. The medulla (central canal) is continuous and wide also.
In a nut shell, by using a strand of hair found in the crime scene, the sex and also the race of victim can be identified. If DNA is extracted from the follicle cells’ nucleus (if found), it can be searched in the database if there’s any similar DNA, then the victim can be identified.
Figure 7: Forcibly removed hair may have tissue attached to itForensic Botany
Forensic botanists look to plant life in order to gain information regarding possible crimes. Leaves, seeds and pollen found either on a body or at the scene of a crime can offer valuable information regarding the timescales of a crime and also if the body has been moved between two or more different locations. Besides, it incorporates several sub disciplines such as dendrochronology (the study of tree rings), systematics (the classification of plants), ecology and forensic palynology (the study of pollen). These can produce specific findings of location of death, decomposition and time of year.
http://www.sfu.museum/forensics/trim/s/videos/bo_role_forensic_botanist-en-VMC3_Flash_Gamma.mov
Blood Stain Analysis
The examination of the shapes, locations and distributions patterns of bloodstains in order to provide and interpretation of the physical events by which they were created that is based on the premise that all bloodstains patterns are characteristic of the forces that have created them.
The blood stain can be analysed through chemical and physical considerations. Upon exiting the body, bloodstains transit from bright red to dark brown, which is attributed to oxidation of oxy-haemoglobin (HbO2) to methaemoglobin (met-Hb) and hemichrome (HC). The fractions of HbO2, met-Hb and HC in a bloodstain can used for age determination of bloodstains and can be measured by Reflectance Spectroscopy. Once blood has left the body it behaves as fluid, gravity acts on the blood, given the right circumstances blood can act according to ballistic theory. Viscosity and surface tension of the blood can also help to determine how it behaves and lead to recreation of crime.
These are the general categories of bloodstains :
Drip Stains/Patterns
(caused by the force of gravity only)
Transfer Stains/Patterns
(a blood contaminated object(s) contacting a surface)
Spatter Patterns (impact, cast-off, etc.)
(liquid blood, internally or externally, subjected to a force greater than gravity)
Blood spatters can indicate important information such as:
- Type and velocity of weapon
- Number of blows
- Handedness of assailant (assailants tend to strike with their dominant hand on the opposite side of the victim's body)
- Position and movements of the victim and assailant during and after the attack
- Which wounds were inflicted first
- Type of injuries
- How long ago the crime was committed
- Whether death was immediate or delayed
Impression Evidence
Impressions are used to find legitimate matches and the practice works the same way as fingerprinting. There are three main types: Footprints (or shoe impressions), Tire tread impressions and Tool markings.
Impressions are left on hard surface by creating electrostatic charges. Simply sprinkling fingerprint dusting powder over recent footprints will attract powder to the charge and create visual image. However, residual static charges don’t last very long and can be easily upset so forensic experts rely more on the deformation of surface areas. Shoe impressions on materials such as soil, sand or snow can produce a largely three-dimensional footprint. While stains and other residue will leave two-dimensional marks and create a recognizable image. Tire marks are much easier to identify. Defects and wear on a tire tread caused by nails, gravel, and patches can identify a unique set of tires. Lastly, tool marks are created when a tool comes into contact with another object or surface and leaves a significant impression.
Forensic Odontology
Tooth identification
The teeth remain long after all other parts have decayed is because the tooth enamel is harder than any other substance in the human body. Enamel can withstand temperatures of more than 2000 degrees Fahrenheit. Teeth are fragile and may shrink especially through intense heat, but they can be preserved with lacquer and used for identification. Dental work (partial od gold crown) will be distorted by fire but still can aid in identification.
Bite Mark Analysis
Bite marks can be detected on the victim or the perpetrator, or on foodstuffs found at the scene of the crime, when the marks were compared to dental impressions taken. The first step in analyzing the bite is to identify it as human as animal teeth are very different. Then, forensic dentists will take measurements of each individual bite mark and record it. Bite photography must be conducted precisely, to accurately depict the orientation, depth and size of the bite. The bite marks on deceased victims are cut out from the skin and preserved in formalin. Forensic dentists then make a silicone cast of the bite mark. The movement of a person’s jaw and tougue when he or she bites contributes to the type of mark that is left. It is not typical to find bite marks with both upper and lower teeth. Forensic dentists use several different terms to describe the type of bite mark:
Abrasion - a scrape on the skinArtifact - when a piece of the body, such as an ear lobe, is removed through biting
Avulsion - a bite resulting in the removal of skin
Contusion - a bruise
Hemorrhage - a profusely bleeding bite
Incision - a clean, neat wound
Laceration - a puncture wound
The bite mark evidence
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