U091105H_C4_PDF

GEK1542 Report

An Overview of Fingerprinting and Presumptive Blood Testing

Name: Seleena Bte Maidin

Group: C4

Matric no.: U091105H

Content Page

1. Introduction

2. History of Fingerprinting 3. Methods of Fingerprinting and Presumptive Tests 4. Analysing the difference between ninhydrin prints 5. Analysing latent old and new toe prints 6. Analysis of patterns of inked fingerprints and toe prints 7. Comparison between fresh fingerprints developed by black and magnetic

powder and with inked prints 8. Comparing the effectiveness of fingerprinting and blood test methods 9. Results and analysis of the Kastle- Meyer test 10. Essay on Fingerprints and Identical Twins

1. Introduction

Fingerprints have become important in our daily lives. From public domains such as the crime and law enforcement, administration, banking organisations to private domains such as privileged information access and inheritance, fingerprinting is highly regarded as a valid source of identification. This is because our fingerprints are one of the few physical traits of ours that differentiates us from each other and doesn’t change throughout our entire lifespan. Two key features of fingerprints that make them so useful as identification sources are their uniqueness and immutability. Even studies of the most identical of twins have shown that fingerprints are never alike to each other. This report aims to provide a holistic overview on fingerprinting and its associated categories such as presumptive blood testing by featuring its history, commonly used techniques and methods, and attempt to compare and contrast between some of these techniques such as ninhydrin, black powder, magnetic powder, ink fingerprinting and the Kastle-Meyer test, as well as provide an insight as to why having identical DNA does not equate to having identical traits especially fingerprints.

2. History of Fingerprinting

In prehistoric times, fingerprinting was used in places like ancient Babylon and Persia for official purposes such as for business transactions and administrative documentation. In 1686 and 1823, two anatomy professors called Malpighi and Purkinje noted the main ridge patterns of fingerprints such as loops respectively. In 1863, a paper was published on how fingerprints of crime suspects can be ‘fixed’ by iodine fuming and then in 1880, the first latent print classification system was invented by Dr. Henry Faulds and published a paper discussing the usage of fingerprinting as a means of identification. In 1883, a murderer was identified by his fingerprint and tried in court. In 1888 British anthropologist Sir Francis Dalton began studying fingerprints as a way of identification. In 1891, the first fingerprint file system was introduced based on Dalton’s study of fingerprint pattern types. In 1897, the world’s first fingerprint bureau was established in Calcutta. In 1900, Sir Henry published a book on using fingerprints as a means of identification and this was implemented in 1901 and 1903 in Britain and America respectively. In 1915, the International Association of Identification was formed. In 1918, Locard stated that 12 points were the same between two fingerprints, then they could be considered belonging to the same person.1 In 1977, the world’s first certification program for fingerprint experts called the IAI's Latent Print Certification Board was established.1 In 2005, Interpol’s automated fingerprint identification system (AFIS) repository exceeds fifty thousand fingerprint sets from over a hundred and eighty four countries. In 2010 IAI recognised advances in fingerprint science, removed the band on qualified identification conclusions and welcomed the idea of future validation and certification of probability models regarding finger or palm print comparisons.1

3. Methods of Fingerprinting and Presumptive Tests

Fingerprints may be detected through optical detection methods such as UV light. One of the most traditional methods used for fingerprints on non-porous surfaces is powdering as the powder will adhere to the sweat and oil residues of the prints. Powder formulations may also be modified to suit the situation for instance, the application of a coloured stain can make luminescent powder which is suitable for multicoloured surfaces. Magnetic powders may also be used on some porous surfaces however in order to avoid chemical treatment or smudging. Ninhydrin and its analogs are also commonly used on porous surfaces and developed marks are dark purple. Latent prints may also be developed on paper by treatment with the amino acid sensitive reagent DFO. However, heat must be applied to quicken the reaction.2 Physical developer (PD) is a fingerprint processing technique for porous surfaces that is sensitive to the water-insoluble (sebaceous) components of the latent fingerprint deposit thus making it useful for surfaces with are wet.2 Other techniques include iodine fuming and latent prints absorb the iodine to produce a brown mark. This method is suitable for both porous and non-porous surfaces. However, iodine is toxic.

In order to identify fingerprints in blood, amido black is a protein stain that may be applied to fingermarks in blood to improve contrast. Blood marks are treated with a methanolic version of this stain. In addition, the reagent 3, 30-diaminobenzidine (DAB) is a sensitive alternative to protein stains for the enhancement of fingermarks in blood.2

Commonly used presumptive blood tests are luminol sprays and Kastle-Meyer test whereby samples turn pink if blood is present. Luminol tests only result in light emission rather than colour changes.3

4. Analysing the difference between ninhydrin prints

Ninhydrin is one of the most widely used chemical reagents in fingerprint detection, especially for the development of latent prints on porous surfaces. The tricarbonyl compound exists as a hydrate in the presence of water to react with ammonia and amines, forming a dark purple product known as Ruhemann’s Purple.4 The formation of Ruhemann’s purple involves three general steps – firstly, the initial attack of the amine function on ninhydrin, secondly, the oxidation and reduction steps that result in intermediates along the pathway, and thirdly, formation of the product Ruhemann’s purple from these intermediates. A mechanistic description of the product’s formation has to accommodate the fact that amino acids react faster than amines with ninhydrin.4 In addition, amino acids attach well to cellulose, which is the main substance in wood-derived products such as paper and cardboard, making them useful and suitable for analysis. They are also relatively stable, thereby allowing prints to be developed long after they were originally deposited.5

Comparing the differently dated ninhydrin prints, the trend observed shows that the prints taken on the 14th of September are clearer and more visible than the prints taken earlier on the 7th as the ridge details were more visible and there was better contrast.

However those that were taken on the 7th were the least visible and had poor fingerprint development as the contrast was poor and very few ridges could be seen. Plus, some of the prints were partial such as the left thumbprint taken on the 7th and the right one taken on the 14th were partial while those taken on the 17th were barely visible. The difference in clarity and completeness of the prints could be attributed to a number of factors such as temperature, humidity, pressure exerted by the fingers on the surface of contact and the time of contact and amount of sweat transferred.6 The warm and dry temperature when the prints were taken could have absorbed more moisture and oily residues from the older prints on the 7th as they were exposed to the environment longer than the prints taken on the 14th, thereby reducing the clarity and visibility of the older prints. In addition, the dryness of the fingers could also be a factor in explaining why the prints on the 17th were barely visible i.e. the lesser the moisture and residues present on the skin ridges, the lesser the amount of sweat transferred to the paper for analysis. Plus, the insufficient amount of deposition pressure exerted could also be another reason for the lack of the prints’ visibility or the presence of partial prints. Thus under ideal conditions such as fresh fingerprints on white paper, ninhydrin provides relatively good contrast but doesn’t work as optimally on aged prints or coloured paper.4

5. Analysing latent old and new toe prints

Latent prints contain a mixture of natural secretions from three types of glands: the eccrine and apocrine gland which makes up the sudoriferous glands, and the sebaceous gland.7 The composition of these secretions and how they are influenced by environmental factors is important in order to effectively detect toe prints, in this case. Such factors which affect the viability and quality of the prints also consist of conditions that encompass the surface of contact and the friction ridges on the subject’s skin. The conditions can be classified as pre-transfer, transfer and post-transfer conditions i.e. the condition of the subject’s ridges as well as the type and amount of residue on it, the conditions that govern the competence of the prints, and the environmental conditions that affect the prints’ clarity after deposition respectively.7

Both the aged and new toe prints were non-recoverable and no latent prints could

be observed. This could be due to factors present in all three areas that interfered with the development of the prints. An example of a pre-transfer condition is the contact of the subject’s feet with a wet surface prior to depositing the toe prints could have resulted in the removal of the oily residues on the ridges of the skin thereby leaving a barely visible print. A transfer condition that might have affected the results was that the subject’s feet might have used insufficient deposition pressure i.e. the pressure applied during contact which includes lateral force causing the prints to be faint and unclear. Another factor i.e. post-transfer condition that could have affected the visibility of the prints was that the weather was cool and dry. As the prints are composed almost entirely of water when they are deposited, the rapid evaporation of moisture might have dried them out, altering certain reagents’ ability to visualize the print such as fingerprint powder.7 This is because fingerprint powders are the least sensitive among the techniques accessible, “with 500 to 1000 ng of material required in the latent mark for successful detection”8.

However, hypothetically, the results should have supposedly been that the older the latent print, the less visible and clear it is. This is because as the age of the toe prints’ residue increases, the moisture and oily particles tend to evaporate leaving the deposition more viscid. Thus, aged prints are relatively difficult to develop by powder technique viscid as the method depends on the physical adherence of the fingerprint powder to the skin ridge deposits.9 Similarly, the same phenomena occurs in warm climates for instance Singapore. However, the drying rate is not reliant on the relative humidity signifying that the sweat residue has a low water content near the surface.9 Another reason for the decreased visibility in older prints could be due to volatilisation or degradation whereby fatty acids break down to more volatile, shorter chain fatty acids indicating the presence of oxidation mechanisms10. Finally, other factors such light and chemicals in the air may cause other reactions such as racemization, evaporation, absorption or adsorption within the latent prints.

6. Analysis of patterns of inked fingerprints and toe prints

Comparing within Table 1 below, it can be observed that excluding the left ring finger, the

fingerprints have an ulnar loop pattern, which can be described as a loop in which the ridges

flow in the direction of the little fingers and turn back on themselves, thereby exiting in the

same region in which they enter.11 The name of this loop is derived from the word ulna

which is a bone in the forearm. The large number fingerprints with this pattern can be

attributed to the fact that the most common pattern

is the loop, that is found in between 60 and 65 percent of all humans.12 Most loops present

are usually ulnar loops and radial loops (similar to the ulnar loop except that the direction

the ridge exits is towards the thumbs) are commonly found only on the index finger.13 The

lateral pocket loop on the left ring finger however, is a composite as it contains a

combination of patterns and can be described as twin loops whose core points have their

exit ends on the same side of one of the deltas.14 Its frequency is also much more rare.

In addition, looking at the general trend of the prints’ clarity, it can be observed that

while most of the prints are visible, the ridges are of low quality and not very clear, with

some blotching. This could be due to insufficient usage of ink which rendered the ridge

patterns indistinguishable, or due to excessive perspiration on the fingers of the subject that

might have inhibited the ink from adhering to the fingers, resulting in a blurred and not very

accurate outcome.15 However, as the objective was to simply deduce the fingerprint

patterns, it must be noted that the blotching did not occur within the core and delta areas,

so it was still possible to accurately determine the fingerprint patterns. In addition, the

partial print of the little finger might have been due to the finger being placed too loosely

such that the finger wasn’t fully rolled from side to side.

Hand Finger Fingerprint Pattern Clarity

Right Thumb Ulnar loop Visible

Index

Middle

Ring

Little

Left Thumb Ulnar loop Visible

Index

Middle

Ring Lateral pocket loop

Little Ulnar loop Partial

Table 1: Classification of inked fingerprint patterns and their clarity

Comparing within Table 2 however, most of the toes had a plain arch pattern, which

can be described as a smooth wave, rounded at the top and lacking pointed ends.11

Interestingly, the most common pattern in the toe prints is only found in 5% of

fingerprints.13 However, this phenomenon seems to be anomalous as research claims

that toe prints work in the same way as fingerprints do12, so the commonality of their

patterns should not be much different from each other.

In addition, looking at the general trend of the prints’ clarity, most of the toe prints

are visible but like the fingerprints, the ridge patterns are of low quality and two of the

toe prints are hardly recoverable but this could be due to the same problems as stated

earlier regarding the fingerprints i.e. insufficient use of ink and excessively wet hands.

Foot Toe Toe print Pattern Clarity

Right Big Plain arch Visible

Four

toes

All plain arch except for middle toe

which is lateral pocket loop

Left Big Plain arch Visible

Four

toes

All plain arch except middle toe

which is ulnar loop

All visible except middle and

fourth toe which are unclear

Table 2: Classification of inked toe print patterns and their clarity

In comparing between Table 1 and 2, the clarity of the fingerprints is much better as

compared to the toe prints perhaps because it is easier to adjust the amount of pressure

being placed on the fingers as compared to the toes, and it is also easier to keep fingers

securely placed and roll them fully from side to side as compared to controlling the toes.

What both the fingerprint and toe print patterns have in common though is that

most of them seems to adhere to a particular pattern which are actually derived in the

same manner i.e. have the same origin of development. Fingers and toes develop small

friction ridges which randomly form unique patterns when the foetus stretches its

fingers and toes in the womb during gestation (week 10-24 of pregnancy), causing the

skin to tense up. These ridges have sweat pores that excrete body fluids like perspiration,

salt and oils which leave latent fingerprints when they come into contact with surfaces.16

As the patterns are found on the inner layer of the epidermis, they are very difficult to

get rid of or change and an attempt to do so usually results in scarring, thereby making

the individual’s prints even more noticeable. Moreover, they do not change and remain

on the individual’s body till it decomposes, thereby making fingerprints and toe prints

immutable. These patterns which are direction-oriented contain features such as

minutiae and singular points which can be further subdivided into core and delta points.

Core points are concentrate areas where there is a local maximum convergence of the

ridge curvature while delta points occur when the convergence is at a local minimum.17

Singular points are pertinent in classifying ridge patterns as they are the key markers

that indicate where ridge patterns converge or diverge. Minutiae on the other hand can

be seen as local distortion of the ridges which diversifies the ridges and prevents them

from being identical, thus enhancing the uniqueness of fingerprints. According to Henry,

the variability of fingerprints enables them to be distinguished based on their

physiological differences into three major categories: arch, loop or whorl, and which can

be further subdivided depending on the differences present within each group.18 Hence,

both fingerprints and toe prints possess patterns which are unique and immutable,

which enables them to be used for identification.

7. Comparison between fresh fingerprints developed by black and magnetic powder and with inked prints

The prints that were developed using black powder are generally visible but are a lot darker as compared to the inked prints in annex C and the prints developed using magnetic powder in annex E. How the powder formulation attaches itself to the fingerprint residue is ruled by the pressure deficit mechanism i.e. “if a powder particle is wetted only on its lower side by the sweat deposition, then owing to the curvature of meniscus there will be a pressure deficit inside the droplet”, causing the adherence of the particulate.9 In other words, due to frictional charges, the electrostatic forces of attraction between the sweat residue and the powder particles also have a role in adhesion, despite it being a minor one. The darker prints also cause the prints to have decreased clarity as the ridges are less defined. The prints are also predisposed to smudges and streaking which decreases their quality. This is because the brush’s contact with the print has unavoidable damaging effect so that exercising a certain amount of care when dusting is important. In this case, too much force and pressure has been exerted on the brush causing dark streaks across the paper and

prints. Estimates claim that approximately ten percent of latent prints developed by using conventional powder dusting techniques at crime scenes are hard to identify.9 In addition, the individual prints are relatively clearer than the when prints are taken simultaneously as the simultaneous prints are either partially visible or are barely visible. This is perhaps because it is easier to exercise control on the depositional pressure when each finger is individually pressed on the paper as opposed to many fingers simultaneously being pressed to make a print on the paper.

On the other hand, the use of the fingerprints developed using the magnetic powder are generally much clearer than the prints in annex C and D as the prints have better contrast and the skin ridges are much more defined and visible. Magnetic powders, or magna-powders as they are sometimes called, are made by combining coarse, spherical iron particles in the conventional powders that are used for dusting. The magnetic iron acts as a carrier for the non-magnetic formulation, forming a brush when a magnetized applicator picks up the powder and upon brushing, only the fine particles of the formulation adhere to the fingerprint residue.9 Once the print has been developed, withdrawing the magnetized steel rod detaches the excess powder from the applicator. In addition unlike inked prints and black powder prints, there was no blotching or streaking respectively as magnetic powders are usually used to avoid the problem of smudging9.

However, the prints that were taken simultaneously, like the toe prints in annex C and some of the fingerprints in annex D, were much more unclear than the prints taken individually in terms of less clearly defined ridges. This could be due to insufficient pressure when depositing prints and as aforementioned it is harder to control the pressure used when prints are taken simultaneously as compared to individually. Interestingly, another common trait is that the simultaneous prints that are poor in clarity come from the left hand. This could be due to the fact that the subject who deposited the prints is left-handed so her ability in using her left hand to stabilize her right hand when taking right-handed prints was more effective than her ability to use her right hand to stabilize her left hand when taking left-handed prints. Hence, there was better control over the pressure exerted for right handed prints taken simultaneously and so those prints were clearer than their left handed counterparts.

8. Comparing the effectiveness of fingerprinting and blood test methods

Method Advantage Disadvantage Ninhydrin • Works well even on dried-

out latent prints • Application can be done in

many forms – dipping, spraying, or brushing

• Works well on porous surfaces

• Carcinogenic

Black powder • Simple to use and develop, obtain results immediately

• Cost effective • Works only on porous

surfaces

• Toxic • Do not work as well on dried-

out latent prints

Magnetic powder

• Simple to use and develop, obtain results immediately

• Luminescent in a wide array of particulate size, colour and composition

• Powder formulations can be modified to suit the circumstances

• Cost effective • Works well on non-porous

surfaces or some porous surfaces

• Non-toxic • May interfere with DNA

amplification, or lower final DNA yield

Ink fingerprinting

• Inexpensive • Reliable • Fast Results • Multi-faceted usage -

criminal, commercial, financial and civilian identifications

• Acts as a deterrent to crime and fraud

• Worldwide computerized systems and established databases extremely valuable during criminal investigations.

• Form of identification that is consistent and unalterable

• Usage of an inappropriate texture of ink can result in running of the ink and pattern distortion

• Prints can be smudged or

blurred, rendering false pattern of prints

• Excessive perspiration on

fingers may inhibit the ink from adhering producing an inaccurate and blurred outcome

KM test • Can detect even minute traces of blood present

• Not test-specific, problem of false positives

Table 3: A table comparison of fingerprinting and presumptive blood testing methods

9. Results and analysis of the Kastle- Meyer test

The results are samples containing blood, beetroot and raw cabbage turned pink. The colour change was gradual rather than sudden and appears to be associated with the colour of the material in the stain. The beetroot and raw cabbage results can be declared as false positives. Although the colour of the grape and Ribena samples can be confused with that of the false positives, they are actually test negative, like ketchup.

The Kastle-Meyer test is a presumptive blood test commonly used in forensic science in order to detect the presence of blood, specifically haemoglobin – an iron-containing protein whose function is to transport oxygen in the blood from the lungs to the rest of the body. In the test, phenolphthalein which has been reduced by two electrons and pre-dissolved in alkaline solution, is used as an indicator for in the presence of blood, and its oxidation is catalysed by the peroxidase-like activity of haemoglobin, causing phenolphthalein to turn from colourless to pink.19 Swabs of samples were treated with a drop of ethanol in order to increase the sensitivity and specificity of the reaction brought about by the cells’ lysis, a drop of chemical indicator phenolphthalein, followed by a drop of hydrogen peroxide, and then observed for any colour change within a time frame of thirty seconds. The time frame is important as after that, most samples will turn pink due to natural oxidation with the air. However, the test is said to be presumptive as it can also give false positive results if other reducing agents are present in the sample such as vegetable peroxidases in the beetroot and cabbage, so it is not test specific for blood and requires other confirmatory tests like the Ouchterlony Test to determine the species of the blood.19 The mechanism of the reaction is as follows - in the presence of blood, hydrogen peroxide reacts with haemoglobin causing the heme centre of the haemoglobin to undergo homolysis of its oxygen bond. The phenolphthalein that has been reduced does not participate initially in this first step. In the second step, the products of the previous reaction are each one equivalent of a high-valent iron-oxo species and hydroxyl radical either of which can oxidize the reduced phenolphthalein back to its coloured form which is pink.19 The amount of acid produced in this reaction is considered insignificant as compared to the base concentration present in the phenolphthalein reagent solution. In addition, catalytic reaction between the heme and hydrogen peroxide causes the test to be sensitive to even minute quantities of blood present in the sample.19

While the test is useful for quick and easy testing for the presence of blood, there have been some concerns about its possible carcinogenic properties, although, it is still considered to be relatively safe and definitely much safer than benzidine, which was once widely used for blood identification but abandoned due to known carcinogenic properties.20

10. Essay on Fingerprints and Identical Twins

Identical twins, or monozygotic twins, are the outcomes of a single fertilized egg dividing into two separate cells and developing into two individuals. Thus, identical twins can be said to share their identical genetic material. Across various populations, the percentage of such individuals is approximately 0.4 %.21 In fact, fertility treatments and advancements in medicine and technology have resulted in an increase in the birth rate of identical twins, according to a study by Robert Derom22.The assumption that many people make however is that identical DNA will result in identical genetic expression and thus identical fingerprints. However, having identical DNA is not the same as having identical fingerprints because various internal mechanisms in the development of the foetus as well as external environmental factors cause differences to occur between identical twins thereby enabling them to be distinctive individuals for identification. The importance of the uniqueness and distinctiveness of fingerprints is evident especially since fingerprinting is one of the most common forms of identification used in public domains such as passports and private domains such as privileged information access and is particularly crucial in areas

like criminal identification as cases have been reported where an identical twin was sentenced for a crime that was committed by his/her sibling22.

Firstly, biological organisms are in general the product of interactions between genes and the environment. Physical traits such as fingerprints are no exception to this rule. The general traits of the fingerprints appear due to the differentiation of skin on the fingertip and the ridges on the foetuses’ fingertips are fully formed at the end of seven months and do not change during the individual’s entire lifetime. This is because the ridge patterns occur on the inner surface of the epidermis layer so even with cuts and bruises, the ridge pattern is embedded so deeply in the skin that it does not change, and those who attempt to alter their fingerprint only end up scarring themselves, thus making their fingerprints even more obvious. However, despite the general traits, what differentiates the fingerprint ridges even more is the different microenvironments that cells on the fingertips grow in as the foetus develops. This is due to the changes in the amniotic fluid flow around the foetus and the foetus’s position in the uterus.22 The finer details on the fingertips are thus varied and are diversified even more by the differentiation of the skin cells. Thus fingerprint patterns between identical twins can never been identical as the processes that govern them are random.

Secondly, the fingerprint patterns of identical twins differ according to their ridge patterns which are comprised of minutiae and singular points, and these in turn are comprised of various core and delta points. The three main types of ridge patterns are arches, loops and whorls. As fingerprints of identical twins are differentiated from the same genes i.e. both will most likely have similar general ridge patterns for instance, if one twin has an arch pattern, the other twin would have an arch pattern too. Hence one has to look into the finer details of the ridge patterns in order to determine their differences such as the position and direction of these minutiae points for instance end points and bifurcation points which are commonly used in automated fingerprint identification systems (AFIS).21

Thus, identical twins do not have exactly the same fingerprints despite having identical DNA. They may have similar general finger ridge patterns but the micro details of these ridges are different and unique. With the growing emphasis on the usage of technology such as biometric systems, these systems should ensure that their level of distinguishing people’s prints is detailed enough so that even identical twins can be distinguished.

___________________________________________________________________________

References:

1. Ed German, The History of Fingerprints, http://www.onin.com/fp/fphistory.html, (Sep. 15, 2010)

2. Suzanne Bell, Encyclopedia of Forensic Science - Facts on File Science Library, (New York: NY Facts on File, 2008), 151-163

3. Madeleine M. Joullie, Tracy R. Thompson, Norman H. Nemeroff, Ninhydrin and Ninhydrin Analogs. Syntheses and Applications”, Tetrahedron 47 (May 1991): 8793

4. Madeleine M. Joullie, Tracy R. Thompson, Norman H. Nemeroff, Ninhydrin and Ninhydrin Analogs. Syntheses and Applications”, Tetrahedron 47 (May 1991): 8791-8830


6. Om P. Jasuja, M.A. Toofany, Gagandeep Singh, G.S. Sodhi, “Dynamics of latent fingerprints: The effect of physical factors on quality of ninhydrin developed prints — A preliminary study”, Science and Justice 49 (Aug 2008): 8-11

7. Brian Yamashita, Mike French, Latent Print Development Chapter 7, www.ncjrs.gov/pdffiles1/nij/225327.pdf (2010)

8. Chris Lennard, The Detection and Enhancement of Latent Fingerprints, www.interpol.int/Public/Forensic/IFSS/.../SpecialPresentation.pdf (Oct 19 2001)

9. G.S. Sodhi, J. Kaur, “Powder method for detecting latent fingerprints: a review”, Forensic Science International 120 (Nov 2000): 172-176

10. Nia E. Archer, Yannis Charles, Julia A. Elliott, Sue Jickells, “Changes in the lipid composition of latent fingerprint residue with time after deposition on a surface”, Forensic Science International 154 (Sep 2004): 224-239

11. Ngaire E. Genge, The Forensic Casebook: The Science of Crime Scene Investigation, (US: The Ballantine Publishing Group, 2002), 36-60


13. Julia Frenette, Fingerprint Patterns, http://www.odec.ca/projects/2004/fren4j0/public_html/fingerprint_patterns.htm (2010)

14. Christopher J Lennard, Trevor Patterson of New South Wales PoliceService, Fingerprint Patterns, http://www.policensw.com/info/fingerprints/finger07.html (2010)

15. Fingerprinting.com, Fingerprinting Criticism, http://www.fingerprinting.com/fingerprinting-criticism.php (2010)

16. David A. Katz, Fingerprinting, www.chymist.com/FINGERPRINTING.pdf (2005) 17. Ching-Yu Huang, Li-min Liu, D.C. Douglas Hung, “Fingerprint analysis and singular

point detection”, Pattern Recognition Letters 28 (Apr 2007) : 1937–1945 18. Crimtrac Commonwealth of Australia, Fingerprint Analysis - The Basics,

http://www.crimtrac.gov.au/systems_projects/FingerprintAnalysis-TheBasics.html (2008)

19. M. Cox, "A Study of the Sensitivity and Specificity of Four Presumptive Tests for Blood", Journal of Forensic Sciences 36(5) (Sep 1991): 1503-1511


21. Adams Wai-Kin Kong, David Zhang, Guangming Lu, “A study of identical twins’palmprints for personal verification”, Pattern Recognition 39 (Apr 2006): 2149– 2156

22. Anil K. Jain, Salil Prabhakar, Sharath Pankanti, “On the similarity of identical twin fingerprints”, Pattern Recognition 35 (Nov 2001): 2653 – 2663

Appendix:

Annex A: Latent prints developed using ninhydrin

Annex B: Aged and fresh toe prints developed using black powder

Annex C: Fingerprints and toe prints deposited using ink pad

Annex D: Fresh fingerprints developed using black powder

Annex E: Fresh fingerprints developed using magnetic powder

Sample provided Colour Change?

[Yes / No ]

Indicate the colour

change (if yes)

Colour Change Within how many

Seconds?

1 Blood

Yes Pink 3

2 Beetroot

Subject to changes

Yes Pink 4

3 Cauliflower

Subject to changes

Yes Pink 4

4 ketchup

Subject to changes

No - -

Table 4: KM Test results Table

5 Ribena

Subject to changes

No - -

Documents

U091105H_C4_PDF