195)3 nalosc-,I. for cot)y ilic u@je of Ulc- lnstni--iint -m tntor!-o@,,riti@?-i e--vice. (,.nclo.,;cd for y,3ur use is a (iuplicate itl,,icli yc)u re(luested in.yulu, ie'%It@-,r to us dated 't:lob.-uary 20j 19539 ft(,,search .n an InterroEttion revice mci 1--rucefiure May 1 1953 i'lli(? airl -.Itri r)urn,)nr, of titis !@irojc,.ct i3 41@o or)tain 2 a -@uccesi. ful interrof.-ttion device from the effects ol side-tone to.7,eUier with an appropriate procedure f or It a u se ., I th a minimumi nur@ber of attactunenta* The secondary aim,, being developed in t@ils laboratory, is to obtain MOT-0 easi.ly interprnted voly@,-,ra7h bv of Eiclc,-tono delay in con- jvinction ttic pt)l:i,:,r-tph* delivered to this labcr;itory a more 2 refined side-';,one delay (,:TT,)) instrument on ft'arch 5., 1953, The construction of this now instru-.r-nt Yas reklue3t*d by the lnve:-,+.ifr@itors .@ith the bolief that its r@,finements i;c)ulci climin.-ite s2ome of clifficulties cricountemd in previotis instruments. Iho rafinements conri.-,tod of a vxrl.-il)le ta,,)e 'V,.)Ocd t.,,ii.cli -?as incot-p-.ir;atnd ,.iit-,h the or:A,3r.., ;ind pi-t@2 ),).ck ne.-.td iias@@jm'uly of !,',;-ignrcorde Iri cr(@ex- to ?I t@.,rlrccrd iinit cr)rrilet,2(jly ti -inr-i re.@)uilt -@-itti a variable t@irio speed* @llro ttl(' lii-necord s.ynchronouo motor wa.,i ;.,.ciju,,3ted so as to clrive a disc at varia:i)lo distances fromthe axis. Ttio newl2y constructed drive was free from wow and liad a 1.10 speed ratige wiiich rie.,ant the t-ape a@)eed V;,W,s 3" to 30" pf,,r second. 'rnis provided an ea.-iily adjustable v-triable in the (lei!iy fro-!i 0.0)116 to 0.)LI6 --!oconds, Tii@, @taptiecirti ondlerfi. loop tane d-,.vice was utilized In pl,,@ce of the -.1tiiidrLrd device. In Febt2uarys 1953 the Investigators decided tit.-it possibly better re- sults coulo be obtained if the siibject was not re@,Tiired to wear earphones, 12i, 19rp'3 -,iddit,icTi.-ii to tli,., v i.ri.,11)le-dolly e"4ulp. r-f-nt so tILit it @..-olaid ix, unneco,,ir@ary, for tii(@, c-u@),)-@ct to @e.Lr Tile eliminatioti of ,3tibjectts earptil)nea was acconplistied 'by addiii,, t t t 2 ., w tir6a Tid two exti@rnal. -@pealmrs, microolionoag an tluxiliary anplifierp a- lip, nLterj-ilioiie.-i of t.!)L, 2 t@-pe ,In(i w"ro as tlu-ott -itcr--,)ticnes r-ince nc, Tliii sul)jcc@@lls micropti,@)ne is conilf-*ctA-,d to tlie qlt.,indard KaCn,-@cord am,,)lif'ier, and the a-Vlifier2's -ifter -switch is the .-'I'M off-,me-on stiitch. T)IO ?iagmcord's monitorina Jack is ttle o,.--tlet from t'kiis in,-,trurient a-x4. it is coniected to the auxilixry arlr)lifier by -A intuic' cal)lo. Itie sti2l.).Iecti.,i ,7-.@eecti Fvti:-, throiii;h this to ttie tvo a:.tternal spe-tikerfi, The s(-con(i ttiz-o it -microplione k@y. tiii@ I i c tlL y2 @,Lci t I if-* ertern.,tl J.-ntorro- r-itortr, ciii rx.,vc@r be df@17Vrod. ;inct.) ttio t,,2,-o IY3.ard tiu,@@itph the tito external speakers# the subject wili bo less likely to su-.i)eot that hi.9 voice is bejng delayed because both -roices vUl sound alJ.ke., even ttiough the inlarrog.,itor$6 voice is not delivrd. *2* .,,fcry It a.,3 fc.,un -tornal @peakers riitcli e.ffective in inOuc,,LnF, t,@,e '@TT, effect than one speaker* @lith only, ore speaker the subject c,,tn turn 2his hoad and tocus his tttt.,ntion fr-,),,i Uit- sotirce of Us d,-zlay--,(i :3peech. Tlio be,-,it thrj @@-,Libjccto Ilia vari..xble-do.Lay instrument delivered in M@irch proved to be Vie 2 most durable -,,o far,'tosted becausa of Its imioved eenip and better con- ;n -itiet' tlii-) -int@firrc),.ator i ith rt-n + 2 i).nizes. T!Ag tlila improved instrumfint iiould provie-a a Lx-tter of ttic variable (1@elqy becaiil-o of the:-;e rrfinementso It wa-i believed -Ulat more subject.-% 1.,oii'2ltl I)e. a-ffec@l("l by I.-Ii-i zidV-t,0110 PIIE@no?nt,,iion @,.tthtti:ir, i-@iroved in. in !?,Ctu,@d cririi.li,,l it, 1;a,,i tiii.,nri +@iat the rtjl,,Jr@et3 @i t,mnent h(i itp-re not affi@ated by a prcfdctut-nink-,d 0.20 ,,-rcondn clel@iy -,ter@ ii L Stially not 2 trtio tiir,-uah r,iii@-c, fr,-Ti to i;-t:7 'urttmmores the of 0.20 2 t,o i.,r ilr-i:itrir @-xtc.,tit t,lia-dt2.L,,jy ,4.,i.,3 increared or decre,-ired. ri,,siiltq agita lndic,)ted to tlio tmt.,,,3tig.-ttors th-@it I)ossibly 2 the vabject's amou?-it c)f educatlong intellit,,cnce or soci-ii consci@-unness was Y.-elatoO to @lie am@-,unt if r:Lf f i.ctilty he v --,,,)tt-r-Lenced in f-,3)c,,Aking ,@!ht-n ttio @4,@D instrument @4 -i -s T(,riLings li-i@i i.ri ()f tlir4 ,iore I-tlcrily li@i wtl t.0 c@)nfe'.3s. Ito-4over ny, guilty -iubjecti aunfestied even ttiough tt was (itsct.)vored that -iA 2 their fjt)eecli van un.-tffected by the STD device* o (-,7 ii,@ c-@ i-n a cl Of'qCt, t)f ttl-? @3.ir;c--tg@ne (Joln,@r nt-r -@e, un tlza inroccfi,,tres to be ti.,%Pd 7,.-ith thn '.-M instru-tpnt !%o that coiires-sic)ns cotild be more easily a.-id ren(lil3r obtained. The rerulttv then obtaim-d iqith the v,3riible. c;plty ln-t,ru--oiylt bor@- out bpl2tef a!7 WEIJ, sntirirlii(i,;s nf thr@ nlq-n of iur r. t r rinri, e-- rcce( o r, -I III It was found that a,,-,r)roxim@itely the sn2n' percentage of r-,ailty atibjdcts confessed @4hen t)-it- i.n-;trxvint ii,; ii-reri fcr tl*,@, interroF,,,!tticm i i;!len tl-v- ono firo.(i del.-iir in.,-,tru,-terit. wiq u,,;ed. 'Fr(irm iriocpti:-,ri of tti.Ls contract, @Lo @lay lls 1953 percenta!,e )f cL)nfe,.lsion-@i fr" InLerrof--,atefi mitltv nuh.jr-atm ar,,niintefi to i.nrroxim,itcilv !;6) t-(-. nq-it. 7'it -3 of 56 nt-.,r crtit r,.in c(it)tra--,te-rl to ttie! of' :,ri, 'n.-LI ;.4t is @-incl 31, 1952. !Airing n-ilicir3 licn ni ,i-@,r2p, i-ir@ed on the-so pi-oxiri@itely 62 r*,r cent of thf-, Jjitprrog,,@.itf@,d subjcct,,s rlid c,.;nfor;s to the crim under lnve3tigation* Thua when one reviews the pa.,jt year in its entiz-@-ly,, it appears th.,tt tiie nide-2tone del.-,iy ftld not increite the r)frcont@igc, o,' confe.-@cinns,, hc@n A conf,--i.-iioii iraq -ained by tllp ii,@,c (@,f t!i(i "P')') in,.tril--v--nt, It (]id not -.i@i8teriil.ly r- o;-) ii. i i. great majority of tlios,-t utio did corifens 'wruld ',iave ct)tifessed witliqut the use of' the '-'TD instrum e;ofi-n 2 I proven to bf! 'wrue In two cases wlieng aftc-.r fu.Lij cunfessing, Uie oubjer.-ts ctited fliat Llic-,y tL(I not, cotiftsa e,,xrlier because of the @"fD 2 ajiri thZLt L"@O.T of.,' 0,;LIF 7L,. It In ,-ub,l)(-t@-, @.orL' so -TD effect '@.liat they vier2e nj I o ru be,@ilt'or-till by the _;er ctneorned al)o,,lt Ui@!ir crime and wem not liste@-iL-if, to w@-kat tlio inturrogator atido ',hon rut)jp-ct i@ c' -tr,actcd 0,1 cff'ecto uf ttf- "T!.'p iii-3 lnteri,cg!itortm perr-taslireiie!i,i i@z lo-@L .-rh@ iz@, little ikclilio,.id c;f @lt)tainiri-. a cqnfessiono It isuic ur)'inio2n of the invc:3tif,,itors tti-:@,t ttir! future tiold- veri iittle r, 3 7! -i@-; !I. 1 -il-, t-:tt. r@v w:,!-, tti;,, i iy,7@) iz tL-1 t the i2y, (:13, @lie t ir tL:). r i@ Cii r irv: iL to tliti,px,o,jo@:t -fi o -Lri @u.,s of anq-x7)rs @i3 c)z, noj, SiLUrt-Ler.,nl iong. term and narrative tyne swers) i.@'em exT)erimL-nfed -,iith (lurin6, poly-,lrapti testa @.,Iinn the .,TD instrument i?as al,,io b---inT ,@perateds tIlC J.71 the so that they wer-s mo,e diff'icult to i-riterpret. Tn facts on two occa.,dons 'II$) al,io '4,tia actlially r.!u-fa-tt-ad t-lie of 4,@k(3 i,,-tnii t tu rt., f 4,livy ic Lui.Lli Fi.L!.'LLy. Fur tti(.,se rF,,-anons tlia investigal,.urs belifjw t'4iat tt-,o '-!Tl) in--trument -!Itould rit; tbp u,-ed !Ln conju=tion wit.11 'Uic rolygrapli tlgto