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AnalysisofDistortioninLatentPrintsCourseOutlineV311/2019

Analysis of Distortion in Latent Prints Description and Syllabus

Thisthree-dayworkshopfocusesontheAnalysisphaseoftheACE-V(Analysis,Comparison,Evaluation,Verification)process.DuringtheAnalysisofalatentprint,theanalystisgatheringinformation.Theanalystisdetectingthefeaturestheymayuseduringthecomparison,settingtolerancesforvariationinappearance,anddeterminingtheutilityoftheprint. The ability to detect these features in the latent print and the establishment of tolerances for variation inappearanceareinextricablylinkedtothedistortionpresentinthelatentprint.BiologicalDistortionAnydiscussionoffrictionridgeimpressionsstartswiththefrictionridgeskin.Whatfeaturesdoesithave?Whatisthestructureofthesefeatures?Whichfeaturesarevariableinthepopulationandwhichfeaturesarecommon?Howandwhydothesefeaturesvaryinappearancefromimpressiontoimpression?Whatdoesnormalversusabnormalfrictionridgeskinlooklike?Whathappensduringwoundhealingthatcausesascar?Participantswillstudyimagesoftheskindisplayingvariousdevelopmentalissues(e.g.congenitalridgehypoplasiaanddysplasia)andalterationsofthefrictionridgeskin(e.g.agingandscarring).ContactDistortionTheskinisaflexiblemediumthatdistortswhenittouchesasurfaceanddisplacesresiduewhenitmovesacrossasurface.Themovementoftheskinonthesurfacecausespredictableeffectsontheridgesandfurrowsthatareeasilyrecognizable.Attendeeswillanalyzethedistortioneffectsoflatentprintsplacedonglassundercontrolledconditions.Afteranalyzingthelatentprint,theattendeeswillobservetheactualvideoofthelatentprintbeingdepositedontothesurface.Attendeeswillbeprovidedadifferentparadigmwithwhichtoconsiderdistortion:howtheskinleavesanimpression.Formany,thisisashiftfromtryingtodecipheralatentprintbasedonwhatisexpectedintheknownprint.ResidueDistortionResiduedistortionreferstohowthefollowingaffecttheappearanceoftheridgesandfurrowsinalatentprint:1)typeofresidue,2)placementofresidueonthesurfaceoftheskin,and3)transferofresiduetoasurface.Thissectionofthecourse focuses on themost difficult of visual distortion effects: tonally transitioning ridges. Examples of tonallytransitioning ridges and the causal affects are demonstrated and discussed. Attendees are provided alternativestrategiesforfollowingridgesthroughtonaltransitions.SurfaceDistortionTexturedsurfacescanintroduceproblematicbackgroundnoiseorcreatefalseedgeshapesandporestructure.Theshape of the object and the natural handling can cause unexpected finger height distributions in simultaneousimpressions.Additionally,any impressionwhere thehandand fingersaregraspinganobjectwillhaveclustersofminutiaeinunusuallycloseproximitywhentheclustersareseparatedbyaprimaryflexioncrease.Examplesofthedistortioneffectsofdifferenttypesofsurfaceswillbedemonstratedanddiscussedwithattendees.AnalysisProcessTheanalysis of a friction ridge impressionanswers twoquestions:1) is there sufficient information towarrant acomparisonand2)whatsearchparameterswillbeassignedto theprint (whereandhowto look in theexemplarprints).Theinformationinfrictionridgeimpressionsusedtoanswerthesequestionswillbeexplored.

EvolveForensicswww.EvolveForensics.comAlice@EvolveForensics.comMobile702.769.9469

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AnalysisofDistortioninLatentPrintsCourseOutlineV311/2019

DailySyllabusDay10800–0900 CourseOverviewandIntroduction0900-1000 IntroductiontotheFrictionRidgeSkin1000-1100 EmbryologicalDevelopmentoftheHandsandFeet1100–1200 EmbryologicalDevelopmentoftheFrictionSkin1200–1300 Lunch1300–1400 PhysiologyoftheFrictionRidgeSkin1400–1500 AgingintheFrictionRidgeSkin1500–1600 DamageandDiseaseintheFrictionRidgeSkin1600-1700 MaskingoftheFrictionRidgeSkinDay20800–0900 IntroductiontotheMechanicsofTouch0900-1000 DepositionPressure,Wobble,DoubleTapsandDoubleTouches1000-1100 SheeringStress:SkinDeformationandResidueRe-Distribution1100–1200 Torque:SkinDeformationandResidueRe-Distribution1200–1300 Lunch1300–1400 SequentialMovements:SkinDeformation1400–1500 ChangesinDeformationPressure:MisalignedRidges1500-1600 GroupDistortionProject1600-1700 IndependentDistortionExercisesDay30800–0900 PresentationofGroupDistortionProjects0900-1000 ReviewofIndependentDistortionExercises1000-1100 ResidueDistributionontheSkin1100–1200 DistributionofResidueinLatentPrints1200–1300 Lunch1300–1400 SurfaceDistortion1400–1500 ResidueandSurfaceDistortionExercises1500–1600 AnalysisPhaseofACE-V1600-1700 CapstoneGroupProject

AbouttheInstructor:

AliceWhitehasaBachelorofScienceinBiologyfromtheUniversityofAlaska,Anchorage.Shebeganhercareer in latentprints in1997andhasbeencertifiedin latentprintsbytheInternationalAssociationforIdentificationsince2001.Aliceserved/servesontheScientificWorkingGroupforFrictionRidgeAnalysis,Study,andTechnology;NISTExpertWorkingGrouponHumanFactors inLatentPrints;AAFSStandardsBoard Friction Ridge Consensus Body; RTI's Human Factors SourcebookWorking Group; OSAC FrictionRidge Subcommittee; and the JFI Editorial Board. Alice has published numerous articles and lecturedthroughout theUnited States, Canada, and Europe. This course has original research published by Alice(Maceo)White.