Original Research Paper DETERMINATION OF HAND FROM A FINGERPRINT

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1 Original Research Paper DETERMINATION OF HAND FROM A FINGERPRINT K.R. Nagesh,Professor & Head, Department of Forensic Medicine, Father Muller Medical College, * Pratik Sahoo, Medical Graduate, Kasturba Medical College, * B. Ashoka, Professor and Head, Department of Criminology, School of Social Work, Roshni Nilaya, * *Mangalore , Karnataka, India. Article history Received: June 19, 2012 Recd. in revised form Dec 12, 2012 Accepted on Dec. 18, 2012 Available online Dec 25, 2012 Corresponding author Dr. K.R. Nagesh Phone: drnag2002@rediffmail.com Keywords: Criminalistics; Hand determination; Dactylography; Fingerprints. Abstract Presence of a fingerprint at scene of crime is a valuable clue in identifying the suspect. To define the criteria that can be used conclusively to determine the side of hand from the fingerprint, bilateral rolled-fingerprints of 150 South Indians were studied. In the whorl patterns, slope of an apex ridge, rotation of central ridge, angle between core and delta, position of bisector, ridge tracing and ridge counting were studied and their accuracy in determining the side of hand was assessed. In right hand, the apex ridge had sloping towards right, anticlockwise rotation, the right angle of core is greater, position of the bisector is towards left side of core, ridge tracing is outer or meeting, the ridge count from delta to core is more on left side. Whereas in left hand, the apex ridge had sloping towards left, clockwise rotation, the left angle of core is greater, position of the bisector is towards right side of core, ridge tracing is inner, the ridge count is more on right side. The findings of our study are useful for the investigator to come to conclusion on the hand from which the particular fingerprint is originated JPAFMAT. All rights reserved Introduction Fingerprints are unique and permanent throughout life unless any damage has occurred to the dermal skin layer [1].Fingerprint found at a place of crime is studied in detail and with accuracy for confirming identity of the suspect conclusively. If the prints are complete and in sequence then it becomes very easy to match the fingerprints using various points of minutiae like ridge counting between delta and core, ridge bifurcation, ridge counting etc. [1,2]. During the court proceeding, a question may arise on the side of hand from which the fingerprint has originated at the scene of crime. This could be answered easily had prints of all the fingers were present. But rarely the prints of all the fingers are formed at the scene of crime. Often the fingerprints are ill arranged and invariably incomplete, making it difficult for determination of hand from which the print has originated. Singh et al. have studied the rolled-fingerprints of Punjabi Jaat males and had shown that the whorl patterns are helpful in determining the hand from which the fingerprint has originated [3]. In the present study, an attempt has been made to determine the hand by using whorl patterns of fingerprint in South Indian population and test the accuracies of the previous study by Singh et al [3]. Material and Methods The study sample consists of 150 subjects (75 males and 75 females) belonging to South India and of different age groups. Informed consent was taken from all the subjects. The rolled-fingerprints from all 10 digits were taken on a plain paper using the ink method. Only the whorl patterns were considered for the analysis using the following parameters (Figs. 1 and 2): Slope of an apex ridge: The outermost ridge (outer type line) was traced from left to right side. If the apex ridge curves towards left side near the right delta, it is called left sloping ridge and if slopes out towards the right side near the right delta, it is called right sloping ridge. If the apex ridge shows no distinct slopping it is considered as absent. Rotation of ridge: The central ridge is considered for determining rotation of the ridges. In central spiral ridge pattern, rotation can either be in clockwise or anticlockwise direction. If the central ridge is a concentric or elliptical it has no clockwise or anticlockwise rotation, and 82

2 hence such rotation is considered as absent. Angle between core and delta:the two deltas of a whorl pattern are joined by a straight line and a perpendicular is dropped from the core onto this straight line using a compass. Then a straight line is drawn between core and delta on both sides, and the lines are extended beyond the core. The angles formed at both sides of the core are used for hand determination [3]. Position of a bisector of line joining the two deltas:two arcs were drawn from each delta on both sides. Then join the points formed by the meeting arcs on both sides of the straight line. The position of this bisector to right or left of the core determines the hand [3]. tracing:on tracing the lower type line covering the inner whorl pattern from left delta towards right delta, the terminating segment of the type line is noted as to whether it ends inside or outside the right delta. Then according to the number of ridges intervening between the tracing line and the delta it is classified as inner, outer, and meeting. Inner means the ridges being traced; starting at the left delta, passes inside of the right delta and three or more ridges intervene between the tracing line and the right delta. Outer means the ridges being traced, after starting at the left delta, passes outside of the right delta, and three or more ridges intervene between the tracing line and right delta. Meeting means the ridges being traced, after starting at the left delta, meets the right delta without intervening ridges or with not more than two such ridges inside or outside the right delta [4]. counting: On drawing a straight line simultaneously from the left and right deltas to a core, the number of ridges intersected by it on both sides is counted. Left counting is the count of intervening ridges between the left delta and core is greater. Right counting is the count of intervening ridges between the right delta and core is greater. Results and Discussion In the present study, 1500 rolled fingerprints from 150 individuals were analysed (tables 1 and 2). The ulnar s were the predominant pattern found followed by whorls in both hands, which is consistent with other studies [3, 5]. However, this differs from the study of Banik SD et al., where they observed whorl patterns more predominantly followed by s [6]. Majority of the whorl patterns were observed in the thumb, index and ring fingers with maximum number in the ring fingers in both hands. Similar results were observed in other studies [3,5]. The whorl patterns were analysed to determine the hand using multiple parameters (tables 3 and 4). In right hand, the slope of apex ridge has decisive inclination towards right in 74%, left in 8.5% and absent in 17.5% cases. The right sloping was highest in little finger, followed by ring finger and thumb. Whereas in left hand, the slope of apex ridge has decisive inclination towards left in 78.1%, right in 7.5% and absent in 14.4% cases. The left sloping was highest in little finger, followed by ring and middle fingers. Singh et al observed the sloping similar to our study with highest sloping in the little and ring fingers in both hands [3]. In present study, the rotation of ridges was anticlockwise in 81.7%, clockwise in 3.8% and absent in 14.5% cases in right hand. The anticlockwise rotation was highest in thumb followed by little finger. Whereas, in left hand, the rotation was clockwise in 84.2%, anticlockwise in 2.3% and absent in 13.5% cases. The clockwise rotation was highest in little finger followed by thumb. Similar findings were observed in Singh s study, where higher accuracies were seen in ring and middle fingers in both hands [3]. On studying the angle between delta and core in the present study, the angle on right side of core is greater than left in right hand (85.1%) and the left angle is greater than right in left hand (90.2%). This is in concurrence with Singh s study [3]. In our study, the determination was highest in little finger followed by thumb in right hand, and little finger followed by ring finger in left hand. Whereas in Singh s study, higher accuracies was seen in ring, middle and index fingers in both hands [3]. In present study, position of the bisector is towards left side of core in right hand (83.4%) and towards right side in left hand (90.2%). This is consistent with the Singh s study [3]. In our study, the accuracy of hand determination using the position of bisector was highest in little finger followed by thumb and ring finger in right hand, and little finger followed by ring finger and thumb in left hand. Whereas in Singh s study, higher accuracies were observed in middle, little and ring fingers in right hand, and in middle, ring and index fingers in left hand [3]. In present study, the ridge tracing was outer in 65.1% cases in right hand and inner in 85.1% cases in left hand. Similar observations were made in Singh s study [3]. The accuracy of hand determination using ridge tracing was highest in little finger followed by thumb and ring 83

3 finger in right hand, and in little finger followed by ring and middle fingers in left hand. Whereas in Singh s study, higher accuracies were observed in little and middle fingers in both hands. In present study, more number of ridge counts was found between left delta and core in right hand (82.1%) and between right delta and core in left hand (80.9%). Similar results were observed in Singh s study [3]. The left-ridge counting was highest in little finger followed by thumb and ring finger in right hand, and the rightridge counting was highest in little finger followed by ring finger and thumb in left hand. Whereas in Singh s study, higher left-ridge counting was found in index and middle fingers in right hand, and higher right-ridge counting was found in ring and little fingers in left hand [3]. Conclusion An analysis was done to determine the hand from a whorl fingerprint in South Indians and the results were studied in comparison with previous study [3]. Our findings were comparable to that of Singh et al [3]. The salient features of our study include: The whorl patterns were observed commonly in thumb, index and ring fingers with maximum number in a ring finger in both hands. The sloping of apex ridge towards right, anticlockwise rotation, greater right angle between the core and delta, position of the bisector towards left side of the core, outer or meeting type of ridge tracing, and an increased ridge count between left side delta to core determines the right hand (Fig. 1). The sloping of apex ridge towards left, clockwise rotation, greater left angle between the core and delta, position of the bisector towards right side of the core, inner type of ridge tracing, and an increased ridge count between right side delta to core determines the left hand (Fig. 2). Fig. 1. Whorl print from right hand Fig. 2. Whorl print from left hand Acknowledgement We would like to acknowledge the Indian Council of Medical Research for permitting to undertake this work as a part of Short term research studentship programme. Conflict of interest None Declared References 1. James SH, Nordby JJ. Forensic science: an introduction to scientific and investigative techniques. 2 nd ed. Boca Raton: CRC Press, Pillay VV. Textbook of forensic medicine and toxicology. 14 th ed. Hyderabad: Paras Medical Publishers, Singh I, Chattopadhyay PK, Garg RK. Determination of hand from single digit fingerprint: a study of whorls. Forensic Sci Int. 2005; 152: Field AJ. Fingerprint handbook. Springfield: Charles C Thomas Publisher, Nithin MD, Balaraj BM, Manjunatha B, Mestri SC. Study of fingerprint classification and their gender distribution among South Indian population. J Forensic Leg Med. 2009; 16: Banik SD, Pal P, Mukherjee DP. Finger dermatoglyphic variations in Rengma Nagas of Nagaland India. Collegium Antropol. 2009; 33:

4 Table 1: showing distribution of types of fingerprints in right hand. Fingerprint pattern Thumb Index Middle Ring Little Plain arch 3(2%) 27(18%) 11(7.3%) 6(4%) 1(0.7%) Tented arch 0(0%) 4(2.7%) 2(1.3%) 1(0.7%) 2(1.3%) Radial 1(0.7%) 10(6.7%) 0(0%) 1(0.7%) 2(1.3%) Ulnar 71(47.3%) 55(36.7%) 106(70.7%) 62(41.3%) 123(82%) Whorl 60(40%) 50(33.3%) 27(18%) 77(51.3%) 21(14%) Twin 12(8%) 2(1.3%) 4(2.7%) 0(0%) 0(0%) Lateral pocket 2(1.3%) 0(0%) 0(0%) 0(0%) 1(0.7%) Central pocket 1(0.7%) 2(1.3%) 0(0%) 3(2%) 0(0%) Table 2 : showing distribution of types of fingerprints in left hand Fingerprint pattern Thumb Index Middle Ring Little Plain arch 3(2%) 33(22%) 20(13.3%) 4(2.7%) 6(4%) Tented arch 3(2%) 4(2.7%) 4(2.7%) 2(1.3%) 1(0.7%) Radial 1(0.7%) 5(3.3%) 0(0%) 2(1.3%) 2(1.3%) Ulnar 79(52.6%) 49(32.6%) 89(59.3%) 66(44%) 117(78%) Whorl 44(29.3%) 50(33.3%) 32(21.3%) 68(45.3%) 21(14%) Twin 18(12%) 4(2.7%) 4(2.7%) 4(2.7%) 1(0.7%) Lateral pocket 1(0.7%) 4(2.7%) 1(0.7%) 0(0%) 0(0%) Central pocket 1(0.7%) 1(0.7%) 0(0%) 4(2.7%) 2(1.3%) Table 3: showing whorl analysis in right hand Slope of apex ridge Rotation of ridge Angle between core and delta Position of bisector tracing counting Thumb (N=60) Index (N=50) Middle (N=27) Ring (N=77) Little (N=21) Total (N=235) Right 44(73.3%) 31(62%) 18(66.7%) 60(77.9%) 21(100%) 174(74%) Left 3(5%) 10(20%) 3(11.1%) 4(5.2%) 0(0%) 20(8.5%) Absent 13(21.7%) 9(18%) 6(22.2%) 13(16.9%) 0(0%) 41(17.5%) Anticlockwise 55(91.7%) 37(74%) 22(81.5%) 60(77.9%) 18(85.7%) 192(81.7%) Clock-wise 1(1.7%) 4(8%) 2(7.4%) 2(2.6%) 0(0%) 9(3.8%) Absent 4(6.6%) 9(18%) 3(11.1%) 15(19.5%) 3(14.3%) 34(14.5%) Right 55(91.7%) 34(68%) 23(85.2%) 68(88.3%) 20(95.2%) 200(85.1%) Left 5(8.3%) 16(32%) 4(14.8%) 9(11.7%) 1(4.8%) 35(14.9%) Right 6(10%) 16(32%) 5(18.5%) 11(14.3%) 1(4.8%) 39(16.6%) Left 54(90%) 34(68%) 22(81.5%) 66(85.7%) 20(95.2%) 196(83.4%) Outer 42(70%) 22(44%) 18(66.7%) 52(67.5%) 19(90.5%) 153(65.1%) Inner 5(8.3%) 17(34%) 7(25.9%) 9(11.7%) 0(0%) 38(16.2%) Meeting 13(21.7%) 11(22%) 2(7.4%) 16(20.8%) 2(9.5%) 44(18.7%) Right 7(11.7%) 18(36%) 6(22.2%) 11(14.3%) 0(0%) 42(17.9%) Left 53(88.3%) 32(64%) 21(77.8%) 66(85.7%) 21(100%) 193(82.1%) 85

5 Table 4: showing whorl analysis in left hand. Slope of apex ridge Rotation of ridge Angle between core and delta Position of bisector tracing counting Thumb (N=44) Index (N=50) Middle (N=32) Ring (N=68) Little (N=21) Total (N=215) Right 7(15.9%) 9(18%) 0(0%) 0(0%) 0(0%) 16(7.5%) Left 32(72.7%) 28(56%) 28(87.5%) 61(89.7%) 19(90.5%) 168(78.1%) Absent 5(11.4%) 13(26%) 4(12.5%) 7(10.3%) 2(9.5%) 31(14.4%) Anticlockwise 1(2.3%) 3(6%) 0(0%) 1(1.5%) 0(0%) 5(2.3%) Clock-wise 40(90.9%) 37(74%) 28(87.5%) 56(82.3%) 20(95.2%) 181(84.2%) Absent 3(6.8%) 10(20%) 4(12.5%) 11(16.2%) 1(4.8%) 29(13.5%) Right 4(9.1%) 9(18%) 4(12.5%) 4(5.9%) 0(0%) 21(9.8%) Left 40(90.9%) 41(82%) 28(87.5%) 64(94.1%) 21(100%) 194(90.2%) Right 40(90.9%) 41(82%) 28(87.5%) 64(94.1%) 21(100%) 194(90.2%) Left 4(9.1%) 9(18%) 4(12.5%) 4(5.9%) 0(0%) 21(9.8%) Outer 5(11.4%) 12(24%) 3(9.4%) 3(4.4%) 0(0%) 23(10.7%) Inner 36(81.8%) 36(72%) 29(90.6%) 62(91.2%) 20(95.2%) 183(85.1%) Meeting 3(6.8%) 2(4%) 0(0%) 3(4.4%) 1(4.8%) 9(4.2%) Right 38(86.4%) 32(64%) 25(78.1%) 60(88.2%) 19(90.5%) 174(80.9%) Left 6(13.6%) 18(36%) 7(21.9%) 8(11.8%) 2(9.5%) 41(19.1%) This article can be cited as: Nagesh KR, Sahoo P, Ashoka B. Determination of hand from a fingerprint. J Punjab Acad Forensic Med Toxicol 2012;12(2):