▁be ▁used ▁for ▁instance ▁to ▁see ▁if ▁a ▁person ' s ▁behavior ▁is ▁suspect ▁( looking ▁around ▁fur t ively , ▁" ten se " ▁or ▁" ang ry " ▁fa cial ▁expressions , ▁w aving ▁arms , ▁etc .). ▁ ▁A ▁more ▁recent ▁development ▁is ▁DNA ▁profil ing , ▁which ▁looks ▁at ▁some ▁of ▁the ▁major ▁markers ▁in ▁the ▁body ' s ▁DNA ▁to ▁produce ▁a ▁match . ▁The ▁F BI ▁is ▁sp ending ▁$ 1 ▁billion ▁to ▁build ▁a ▁new ▁bi ometric ▁database , ▁which ▁will ▁store ▁DNA , ▁fa cial ▁recognition ▁data , ▁ir is / ret ina ▁( ey e ) ▁data , ▁finger print s , ▁pal m ▁prints , ▁and ▁other ▁bi ometric ▁data ▁of ▁people ▁living ▁in ▁the ▁United ▁States . ▁The ▁computers ▁running ▁the ▁database ▁are ▁contained ▁in ▁an ▁under ground ▁facility ▁about ▁the ▁size ▁of ▁two ▁American ▁football ▁fields . ▁ ▁The ▁Los ▁Angeles ▁Police ▁Department ▁is ▁installing ▁autom ated ▁fa cial ▁recognition ▁and ▁license ▁plate ▁recognition ▁devices ▁in ▁its ▁squad ▁cars , ▁and ▁providing ▁hand h eld ▁face ▁sc ann ers , ▁which ▁officers ▁will ▁use ▁to ▁identify ▁people ▁while ▁on ▁pat rol . ▁ ▁Fa cial ▁therm ograph s ▁are ▁in ▁development , ▁which ▁allow ▁machines ▁to ▁identify ▁certain ▁emot ions ▁in ▁people ▁such ▁as ▁fear ▁or ▁stress , ▁by ▁meas uring ▁the ▁temperature ▁generated ▁by ▁blood ▁flow ▁to ▁different ▁parts ▁of ▁the ▁face . ▁Law ▁enfor cement ▁officers ▁believe ▁that ▁this ▁has ▁potential ▁for ▁them ▁to ▁identify ▁when ▁a ▁suspect ▁is