B ar r y C . S check ,E sq .P eter J . N euf el d,E sq .D i r ector s M addy del one,E sq .E x ecuti v eD i r ectorI nnocenceP r oj ect 40W or thS tr eet,S ui te7 01N ew Y or k ,N Y 1 001 3 T el 21 2. 364. 5340 F ax 21 2. 364. 5341w w w . i nnocencepr oj ect. or g J ul y22, 201 5 T ex as F or ensi cS ci ence C ommi ssi on 1 7 00 N or thC ongr ess Av enue,S ui te 445 Austi n,T ex as7 87 01D ear C ommi ssi oner s: P l easeaccept thi scompl ai nt,f i l ed on behal f ofour cl i ent,S tev en M ar k C haney , andon behal f oftheI nnocence P r oj ect,I nc. W e askthat theT ex as F or ensi cS ci ence C ommi ssi on("theC ommi ssi on")ex er ci se i tsstatutor ymandatetoi nv esti gateand r epor t on"thei ntegr i tyand r el i abi l i ty "ofbi temar k ev i denceas usedi n cr i mi nalpr oceedi ngs.T ex . C r i m.P r oc. C ode Ann. ar t. 38. 01 (4)(b-1 )(1 ). 1T he I nnocence P r oj ecti sa nati onal l i ti gati onand publ i cpol i cy or gani zati on dedi cated toex oner ati ngw r ongf ul l y conv i cted per sonsthr oughD N A testi ngand i mpr ov i ng thecr i mi nalj usti cesy stemto pr ev entf utur e mi scar r i agesofj usti ce. T o date, 330 peopl ei n theUni tedS tates, i ncl udi ng1 8w hoser v ed ti meon deathr ow , hav e been ex oner ated by D N A testi ng. One l esson tobedr aw nf r omtheseex oner ati onsi s that the mi sappl i cati onoff or ensi csci ences i s oneofthel eadi ngcauses ofw r ongf ul conv i cti on, contr i buti ng to theor i gi nal w r ongf ulconv i cti oni nappr ox i matel yhal f oftheD N A ex oner ati oncases. S ome f or ensi c techni q uesar e mor e pr obl emati cthanother s, how ev er , andofthosedi sci pl i nescur r entl yi n use,i ti s bi temar k compar i sonev i dence that poses themostacute thr eat tother el i abi l i ty andf ai r nessofT ex as'scr i mi nalj usti cesy stem.I ndeed, despi te ther el ati v er ar i ty ofi tsappl i cati on,nol ess than24 peopl ehav e been w r ongf ul l y conv i ctedori ndi ctedon thebasi sofbi temar k ev i dence,2 i ncl udi ng at least IF or ensi c odontol ogy i s notspeci f i cal l yenumer atedasan accr edi tedf i el doff or ensi csci ence.See 37T ex .Admi n. C ode 28. 1 45. How ev er ,i t maybetr eatedas a f or mofi mpr essi onev i dence,see Milam v.State, N o.AP -7 6,37 9,201 2W L1 868458, at*1 2-*1 3 (T ex . C r i m.App. M ay23,201 2)(unpubl i shedopi ni on), w hi chmaythusbeconducted outofan accr edi tedl abor ator y ,gi v i ng theC ommi ssi onaddi ti onalj ur i sdi cti on. See T ex . C r i m.P r oc. C ode Ann. ar t. 38. 01 (4)(a)(3).2 See E x .B (Amanda Lee M y er s,MenWrongly Convicted or Arrestedon Bite Evidence, AS S OC I AT E DP RE S S , J une1 6, 201 3,av ai l abl eat http://new s. y ahoo. com/men-w r ongl y -conv i cted-ar r ested-bi te-ev i dence- 1 5061 0286. html ); E x . C (AmandaLee M y er s, Bites Deridedas Unreliable in Court, AS S OC I AT E DP RE S S , J une1 6, 201 3,av ai l abl eat http://new s. y ahoo. com/ap-i mpact-bi tes-der i ded-unr el i abl e-cour t- 1 5000441 2. html ); see also E x . D(Li st ofB i teM ar k E x oner ati ons).B enj ami nN . C ar dozoS chool of Law ,Y eshi v aUni v er si tytw oi nT ex astodate. 3T hat thi stechni q uei s r esponsi bl ef or so many mi scar r i agesofj usti cei s notsur pr i si ng. As thi scompl ai ntoutl i nes, nov al i datedand r el i abl esci ence r emotel y suppor ts bi te mar k ev i dence,andw hatsci ence ther ei s af f i r mati v el y di spr ov es ev en themostbasi cassumpti onsw hi chunder l i ei t. B i te mar k s,mor eov er ,"of tenar e associ ated w i thhi ghl y sensati onal i zedand pr ej udi ci al cases,and ther ecan beagr eat dealofpr essur eon theex ami ni ng ex per ttomatcha bi temar ktoasuspect,"see E x . Aat1 7 5 (N AT I ON AL AC AD E M YOF S C I E N C E S , C ommi tteeonI denti f y i ng theN eedsoftheF or ensi c S ci ences C ommuni ty ,S T RE N GT HE N I N G F ORE N S I CS C I E N C EI N T HEUN I T E DS T AT E S : A P AT H F ORW ARD(2009)("N AS Repor t")). T hi s,al ong w i ththef act thatbi temar kanal y si s i senti r el y subj ecti v e,gr eatl yi ncr easesther i sk ofw r ongf ul conv i cti oni n bi te mar k cases.Gi v en thecompl etel ack ofsci encesuppor ti ng bi temar k anal y si s, and thegr av e r i sk ofw r ongf ul conv i cti on useofthetechni q ueposes,bi te mar k sr epr esentan i deal and cr i ti caloppor tuni ty f orthi sC ommi ssi on tobr i ng tobear i tsstatutor ymandateto "adv ancethei ntegr i tyandr el i abi l i ty off or ensi csci ence"i nT ex as. See T ex . C r i m.P r oc.C ode Ann. ar t. 38. 01 (4)(a-1 ). W e thusaskthatthi sC ommi ssi on under tak ea thor ough i nv esti gati onofbi temar k ev i dence. Ourr eq uesti s thatthi si nv esti gati oni ncl ude r etr ospecti v eand pr ospecti v ecomponents. Retr ospecti v el y ,w easkthatthi sC ommi ssi on audi t thosecases i n w hi chbi temar k compar i son testi mony w asof f er ed. P r ospecti v el y , w e askthi sC ommi ssi ondecl ar e a mor ator i umon theconti nued useofbi temar kcompar i sonev i dence i n cr i mi nalpr osecuti onsunti l such ti meas the techni q uehas been sci enti f i cal l yv al i datedand pr ov enr el i abl e. D oi ngso w i l l notonl y adv ance thi sbody 's statutor ymi ssi on,butal so hel pensur e thatnomor ei nnocentT ex ans ar ei ncar cer atedas a r esul tofthi sdanger ousl yunr el i abl e"sci ence. " Bite Mark AnalysisHasN everBeen Validated or Proven Reliable T he useofbi te mar k compar i sonev i dencei ncr i mi naltr i al sr estsonaser i es ofunpr ov enassumpti ons. F i r st, bi temar k compar i sonev i denceassumes thatthebi ti ng sur f aces ofteeth(i . e. , thedenti ti on)ar e uni q ue. S econd, i tassumes thathumansk i n i s capabl e ofaccur atel yr ecor di ng thedenti ti on'suni q uef eatur es. T hi r d, i tassumes that f or ensi c denti stscan r el i abl y associ ateadenti ti on w i tha bi temar k . F i nal l y ,bi temar kcompar i sonassumes that,gi v enal lthef or egoi ng,f or ensi cdenti stscan pr ov i dea sci enti f i cal l yv al i desti mate as to thepr obati v ev al ueoftheassoci ati on. B ut,as thi sl etterw i l l demonstr ate, nosci ence suppor ts theseassumpti ons,and thusnosci ence suppor ts the concl usi on thata per petr ator can bei denti f i edf r oma bi temar k i n humansk i n.The Dentition Has Never Been Scientifically Demonstrated to beUnique T he f i r st assumpti onofbi temar k compar i sonev i dence i s thatthehumandenti ti on (i . e. , thebi ti ngsur f aces ofteeth)i s uni q ue. B ut thi spr oposi ti onhas nev er been demonstr atedby sci ence tobe v al i dorr el i abl e. I n 2009, the N ati onal Academy ofS ci ences ("N AS ")-anor gani zati onmadeupofthenati on'smostaccompl i shed 3 F ormor eon theex oner ati onsofC al v i n W ashi ngtonandJ oeS i dneyW i l l i ams,and the pr obabl ew r ongf ulconv i cti onsofS tev en M ar k C haney and other si n T ex as, see b i f r a .2 sci enti sts"char ged[by anActof C ongr ess]w i thpr ov i di ngi ndependent,obj ecti v eadv i ce tothenati ononmatter sr el atedtosci enceandtechnol ogy "4-under took thef i r st ex ami nati onby ani ndependentsci enti f i cbody ofbi temar k ev i dence. Af ter near l y f oury ear sofw or k ,i ncl udi ngthor oughl i ter atur er ev i ew sandex tensi v etesti mony f r omav ast ar r ay of sci enti sts,l aw enf or cementof f i ci al s,medi cal ex ami ner s,cr i mel abor ator yof f i ci al s,i nv esti gator s,attor ney s,andl eader sofpr of essi onal andstandar d-setti ng or gani zati ons,theN AS i ssuedi tsgr oundbr eak i ngandauthor i tati v er epor t. W hi l ethe r epor tcr i ti ci zedthesci enti f i cf oundati onf or many f or ensi cdi sci pl i nes,theN AS r eser v ed i tsmostpoi ntedanddev astati ngcr i ti q uef or bi temar k ev i dence,concl udi ngthatthe techni q uel ack ssci enti f i cv al i di ty andhasnev er beenpr ov enr el i abl e.I npar ti cul ar ,theN AS r ej ectedthef i r stassumpti onofbi temar k anal y si sas basel ess,f i ndi ngthat"[t]heuni q uenessofthehumandenti ti onhasnotbeensci enti f i cal l yestabl i shed. "E x . Aat1 7 5- 7 6(N AS Repor t). Recentsci enti f i cr esear chpubl i shed l ar gel y af ter theN AS Repor tsuggeststhatnotonl y hasthi suni q uenessnot been sci enti f i cal l y establ i shed,butthati tcannot be. T hi sr esear chi ndi catesthatthel i mi ted f eatur esofthebi ti ngsur f acesofteeth,w hi char el i k el y toi nv ol v eonl y onenar r owsur f aceof l essthanei ghtteethw i thi nabi temar k (asopposedto32teethw i thf i v esi des f or aty pi cal adul t),may notactual l y beuni q ue. 5I ndeed,thesestudi eshav ef oundther e ar e"matches"betw eendenti ti onsw i thi ncer tai npopul ati ons.6 See E x . E at,r ,r 8,1 4-1 5 (Af f i dav i tofD r . M ar y andP eter B ush("B ushAf f i dav i t"))("Our r esul tsi ndi catethatthe bi ti ngsur f acesofhumananter i or (f r ont)teeth(i . e. ,thedenti ti on)i snotuni q uew i thi n measur ementer r or . T hi si spar ti cul ar l y tr uew i thi nabi temar k ,i nw hi chonl y those anter i or teethmay bei nv ol v ed. ").Even if the DentitionWere Unique. Human Skin Is NotCapable O(Accurately Recording Those Unique Features E v eni fther ew er esci enti f i csuppor tf or thepr oposi ti onthatthedenti ti oni s uni q ue,ther ei snosuppor tf or thepr oposi ti onthathumansk i ni scapabl eof accur atel yr ecor di ngthoseuni q uef eatur es. T heN AS Repor tf oundthatthi sassumpti on,too,w as unsuppor ted,concl udi ngthat"[t]heabi l i ty ofthedenti ti on,i funi q ue,totr ansf er auni q ue patter ntohumansk i nandtheabi l i ty ofthesk i ntomai ntai nthatuni q uenesshasnotbeen sci enti f i cal l y establ i shed. . . . "E x . Aat1 7 5-7 6(N AS Repor t).M or eov er ,asw i ththesupposeduni q uenessofthedenti ti on,anew body ofsci ence-muchofw hi chemer gedaf ter publ i cati onoftheN AS Repor t-suggeststhat thi sabi l i ty w i l l nev er beestabl i shed. T hi speer -r ev i ew edr esear chi ndi catesthatduetoi ts 4 See N ati onal Academy ofS ci ences, av ai l abl eat http://w w w . nasonl i ne. or g/about-nas/mi ssi on/.5 E x .F (B ush M A, B ush P J ,S heets, HD . S tati sti calE v i dencef ortheS i mi l ar i tyoftheHumanD enti ti on.JF or ensi cS ci201 1 ,56(1 ): 1 1 8-1 23 ( obser v i ngsi gni f i cant cor r el ati onsand non-uni f or mdi str i buti onsoftooth posi ti onsas w el l as matches betw eendenti ti ons));E x . G(S heets HD ,B ush P J ,B r zozow sk i C , N aw r ock iLA, HoP ,and B ush M A.D ental S hape M atchRatesi n S el ectedandOr thodonti cal l y T r eatedP opul ati ons i n N ew Y or k S tate: AT w o D i mensi onal S tudy .J F or ensi cS ci201 1 ,56(3): 621 -626(f mdi ng r andomdentalshape matches));E x . H(B ush M A, B ushP J ,S heets HD . S i mi l ar i tyandM atch RatesoftheHuman D enti ti on I n3D i mensi ons:Rel ev ance toB i temar k Anal y si s. I nt J Leg M ed 201 1 ,1 25(6): 7 7 9-7 84(same)).6 See supra/n.5.3 ani sotr opi c,v i scoel asti c,andnon-l i near pr oper ti es,humansk i ncannotaccur atel y r ecor d w hatev er uni q uenessmay bepr esenti nthehumandenti ti on.7SeeE x . E at ~8 (B ush Af f i dav i t). T hi s w or k demonstr atesthatsk i n'snatur al tensi onl i nes and ti ssuemov ement di stor t bi temar k s,of tendr amati cal l y . 8 B i temar k sf r omthesame denti ti onmay appearsubstanti al l ydi f f er entdependi ngon theangl eandmov ementofthebody andw hether the mar kw as madepar al l el orper pendi cul ar totensi onor Langerl i nes.9Other studi es i ndi cate thatsk i n i sso unr el i abl easa medi umthatsi mi l ar l yal i gneddenti ti onsmay cr eate i ndi sti ngui shabl e mar k s. E v en mor econcer ni ng, thi sr esear chal so r ev eal edthat denti ti onsmay appeartobestmatchmar k stheydid notcreate/'' T hus, cur r ent r esear chstr ongl y suggests that"ev eni fthehumandenti ti onw er e uni q ue. . . humansk i n i s notcapabl e off ai thf ul l y r ecor di ng thatuni q uenessw i th suf f i ci ent f i del i tytoper mi tbi temar k compar i son. "E x . E at~23(B ush Af f i dav i t);see alsoE x . Aat1 7 4 (N ASRepor t)("[B ]i temar k son thesk i n w i l l change ov erti meand can bedi stor ted bytheel asti ci ty ofthesk i n, theunev ennessofthesur f ace bi te,andsw el l i ng and heal i ng. T hese f eatur es may sev er el yl i mi t thev al i di ty off or ensi codontol ogy . ").ForensicDentistsCannotReliablyAssociateADentitionWith ABiteMark T he thi r df al se assumpti onofbi te mar k anal y si si s thatf or ensi c denti stscan r el i abl y associ ate a denti ti onw i tha bi temar k . B utthe N AS f ound that"[t]her ei s no sci ence on ther epr oduci bi l i ty ofthedi f f er ent methodsofanal y si s thatl ead toconcl usi ons about thepr obabi l i ty ofamatch. T hi si ncl udes r epr oduci bi l i ty betw eenex per ts and w i th thesame ex per t ov erti me. "E x . Aat1 7 4 (N ASRepor t). I ndeed, "astandar d f orthe ty pe, q ual i ty ,and number ofi ndi v i dual char acter i sti csr eq ui r ed toi ndi cate thata bi te mar khasr eacheda thr eshol dof ev i denti ar y v al uehasnot beenestabl i shed. "Id.at1 7 6.T hi si s anespeci al l yacute pr obl emi n bi temar k compar i sonbecausethemanner i n w hi ch sk i n heal sordecomposes ov erti mei s not pr edi ctabl e,and ther ef or e ther ei s no methodol ogytoaccount f orthedi stor ti onofthei nj ur ycaused by thesepr ocesses. Asa r esul t,ex per ts attempti ng toassoci ate a par ti cul ar denti ti onw i tha bi temar kmadeon humansk i n can, at best,mak eeducatedguesses.7E x . I (B ush M A,B ush P J ,S heets HD .AS tudyofM ul ti pl eB i temar k sI nf l i ctedi n HumanS k i n by a S i ngl e D enti ti onUsi ngGeometr i cM or phometr i c Anal y si s. F or ensi cS ci ence I nter nati onal 21 1(201 1 )1 -8); E x . J (B ush M A,T hor sr ud K, M i l l er RG,D or i onRB J ,B ushP J . T he Response ofS k i n toAppl i edS tr ess: I nv esti gati on of B i temar k D i stor ti oni n a C adav erM odel . J F or ensi cS ci201 0;55(1 ):7 1 -7 6);E x .K(B ush M A,C ooperHI , D or i onRB J .I nq ui r y i nto theS ci enti f i c B asi sF orB i temar k P r of i l i ngand Ar bi tr ar yD i stor ti onC ompensati on. JF or ensi cS ci201 0;55(4):97 6-983);E x .L(M i l l erRG,B ush P J ,D or i on RB J , B ush M A.Uni q uenessoftheD enti ti onas I mpr essedi n HumanS k i n: AC adav erM odel . J F or ensi cS ci2009;54(4):909-1 4)("M i l l er ,Uni q ueness").8E x . M (B ush M A, M i l l er RG,B ush P J ,D or i on, RB . B i omechani cal F actor si n HumanD er malB i temar k s i n aC adav erM odel . J F or ensi cS ci200954(1 ):1 67 -1 7 6)).9Id 10E. g. , E x .L(M i l l er , Uni q ueness). F or a r eal l i f e ex ampl eofhow w el l ani nnocent per son'sdenti ti on can appeartomatch a bi temar k , see E x .N at p. 46(Ami ci C ur i aeB r i ef ofM i chaelJ . S ak s, T homas Al br i ght, T homasL.B ohan, B ar bar aE .B i er er and34 Other S ci enti sts,S tati sti ci ans andLaw -And-S ci enceS chol ar s and P r acti ti oner sI nS uppor t OftheP eti ti onf or W r i tofHabeasC or pus by W i l l i amJ osephRi char ds ("S ci enti sts'B r i ef ')) andin.fraon thew r ongf ul conv i cti onofRay Kr one.4M or eov er ,w hi l etheAmer i canB oar dofF or ensi cOdontol ogy ("AB F O"), f or ensi codontol ogy 'sonl y boar dcer ti f y i ngbody ,hasi ssued"gui del i nes"f or ar angeofconcl usi onsconcer ni nganassoci ati onbetw eenabi temar k andasuspect,i tsmember s ar enotr eq ui r edtoadoptthesuggestedter mi nol ogy . N or ar ethey pr ov i dedw i thanygui danceondel i neati ngbetw eenthev ar i ousconcl usi ons. M or ei mpor tantl y ,these gui del i nesw er enotar r i v edatsci enti f i cal l y buti nsteadw i thnothi ngmor ethanashow ofhandsofthemember spr esentatameeti ng. See E x . Aat1 7 4 (N ASRepor t)("T he [AB F O] gui del i nes, how ev er ,do noti ndi cate thecr i ter i a necessar y f orusi ngeach method todeter mi ne w hetherthebi te mar k can ber el atedtoa per son'sdenti ti onand w i thw hat degr ee ofpr obabi l i ty . "). As the N AS f ound,"[e]v enw hen usi ng the[AB F O] gui del i nes, di f f er entex per ts pr ov i dew i del y di f f er i ng r esul ts. . . . " Id. Ul ti matel y , the N AS concl uded thatf or ensi codontol ogi stsl ack "thecapaci tyto consi stentl y ,and w i tha hi ghdegr eeofcer tai nty ,demonstr ateaconnecti onbetw een ev i denceand aspeci f i c i ndi v i dual or sour ce. "Id. at7 ; see also id.at1 7 5 ("[T ]he sci enti f i c basi si sinsufficient to conclude that bite mark comparisons can result in a conclusive match." (emphasi s added)).Even !(Bite MarksCould Be"Matched. "There Is No Evidence Of The Probative Value O(ThatAssociation E v eni fther ew er esci ence tosuppor t thenoti onthatanassoci ati oncoul d r el i abl ybemadebetw eenadenti ti onanda bi temar k ,bi temar k anal y si ssti l lf ai l si ni tsf i nalassumpti on-that asci enti f i cal l yv al i desti mate ofthepr obati v ev al ueofthatassoci ati on can be made. B utas theN AS concl uded, ther ei s now aytodeter mi ne thepr obabi l i ty ofa match because"ther ei s noestabl i shedsci ence i ndi cati ngw hat per centageofthe popul ati onor subgr oup ofthepopul ati oncoul dal so hav e pr oduced[a]bi te. "Idat1 7 4; see also E x . E at ,r 28(B ush Af f i dav i t)("[S ]tati sti cal ev i dencef orthel i k el i hoodofa r andommatchi s, as y et,unsuppor tabl e. ").T hi sC ommi ssi on r ecentl ytook acti on r egar di ng pr eci sel ythesame ty peofsci enti f i cal l yi nv al i d testi mony i n casesi nv ol v i ng mi cr oscopi chai r compar i son. Af tertheF B I ack now l edged thati ts hai r ex ami ner s hadbeen mak i ngi mpr operi ndi v i dual i zati oncl ai ms andother w i se ex agger ati ng thepr obati v ev al ueofan associ ati on betw eena k now nandasuspected hai r f ordecades,i t, al ong w i th the N ati onalAssoci ati onofC r i mi nalD ef enseLaw y er sand theI nnocence P r oj ect,under took an unpr ecedented r ev i ew ofthousandsofcases tosear ch f ortesti mony thatw entbey ond the boundsofsci ence.1 1T he F B I al so tr ai nedhundr edsofstate andl ocal ex ami ner s togi v esi mi l ar l yf l aw ed testi mony ,andso theC ommi ssi onhas under tak enacaseaudi t to"deter mi new hether the i ssues i denti f i ed bytheF B I ar e al so pr esenti n thetesti mony pr ov i dedby state, county1 1See, e.g., E x .A at1 60 (N ASRepor t);S pencerHsu,US.Reviewing 27 Death Penalty Convictions for FBI ForensicTestimony Errors, W AS HI N GT ON P OS T ,J ul y 1 7 , 201 3,av ai l abl e at http:!/w w w . w ashi ngtonpost. com/l ocal / cr i me/us-r ev i ew i ng-27 -death-penal ty -conv i cti ons-f or -f bi -f or ensi c- testi mony -er r or s/201 3/07/1 7 /6c7 5a0a4-bd9b-1 1e2-89c9-3be8095f e7 67_stor y . html .5 andmuni ci pal l abor ator i es. "1 2T hi scaseaudi t w i l l consi derw hether 1 )"ther epor tortesti mony contai n[ ed]astatement ofi denti f i cati on";2) "ther epor tortesti monyassi gn[ ed] pr obabi l i ty or stati sti cal w ei ght";3) "ther epor tortesti mony contai n[ ed]anyotherpotenti al l y mi sl eadi ngstatementsori nf er ences. t'':'As theC ommi ssi onhas concl uded,a hai rex ami ner cannotpr ov i deasci enti f i cal l y v al i desti mateofther ar eness or f r eq uency of [an]associ ati on. T heex ami ner 'stesti mony shoul d r ef l ectthef actthathai r compar i soncannotbeusedtomak eaposi ti v e i denti f i cati onof ani ndi v i dual . I nother w or ds,hai r compar i soncan i ndi cate,atthebr oadcl assl ev el ,thatacontr i butor ofak now nsampl e coul dbei ncl udedi napool ofpeopl easapossi bl esour ceofthehai rev i dence. How ev er ,theex ami ner shoul dnotgi v eanopi ni onastothe pr obabi l i ty orthel i k el i hoodofa posi ti v eassoci ati on. 1 4 T hesesame l i mi tati onsappl ytobi temar k ev i dence. See E x .Aat1 7 6 (N ASRepor t).("B i te mar k testi mony hasbeencr i ti ci zed basi cal l y on thesame gr oundsas testi mony byq uesti oned documentex ami ner sand mi cr oscopi chai r ex ami ner s. "). I ndeed, bi temar kev i dence i s ev en mor eci r cumscr i bed,as thedi stor ti ng pr oper ti esofsk i n di scussedabov e mean that bi temar k compar i sonex per tscannotev en v al i dl y mak eanassoci ati on betw een a mar k anda denti ti on.Bite Marks Are Prone toSeriousError Gi v eni ts l ack ofsci enti f i c basi s,i ti s nosur pr i se thatbi temar k compar i son ev i dence i s pr one toser i ous er r or . I ndeed, "er r or r ates by f or ensi cdenti stsar e per haps thehi ghestofanyf or ensi ci denti f i cati onspeci al ty sti l lbei ng pr acti ced. "E x .N at5 (S ci enti sts'B r i ef ). D ev astati ngnewr esear ch hi ghl i ghti ngthesepr of ounder r orr ates, conducted i n par t bytheVi ce P r esi dentoftheAB F O'sow nE x ecuti v eC ommi ttee, has r ecentl ybecome publ i c. T hi sstudy , enti tl edConstructValidity Bitemark Assessments Using the ABFO Bitemark DecisionTree ("C onstr uctVal i di ty S tudy "),demonstr ates that ev en theAB F O'smostex per i enced f or ensi codontol ogi stscannotagr eeon w hether an i nj ur yi s a bi temar k at all, tosaynothi ngofw hether i t w ascaused by a par ti cul ari ndi v i dual .As par toftheC onstr uct Val i di ty S tudy , photogr aphsof1 00 patter nedi nj ur i es w er eshow n to1 03AB F Oboar d-cer ti f i edD i pl omates. T heyw er eask ed todeci de thr ee q uesti ons:f i r st, w hetherther ew assuf f i ci ent ev i dence tor ender anopi ni onon w hetherthe patter nedi nj ur yw asa humanbi temar k ;second, w hether consi stentw i th theAB F O deci si on tr ee, thei nj ur yw as,i ndeed, ahumanbi temar k ,nota humanbi temar k ,or1 2 T ex as F or ensi cS ci ence C ommi ssi on, Statement RegardingTexas Hair Microscopy ReviewTexas Forensic Science Commission, av ai l abl eat http://w w w . f sc. tex as. gov /si tes/def aul t/f i l es/S tatement%20r e%20T ex as%20HM %20Rev i ew %20F i nal %20Dr af t