TWO NEW DEVICES AVAILABLE TO LAW ENFORCEMENT AND SECURITY PERSONNEL, VOICE ID AND PSE, USE THE HUMAN VOICE AS INPUT DATA. THE FORMER HELPS TO DETERMINE THE SPEAKER'S IDENTITY; THE LATTER IS A TRUTH VERIFICATION DEVICE. THE VOICEPRINT ID METHOD IS BASED ON AURAL AND VISUAL COMPARISON OF ONE OR MORE VOICES WITH A QUESTIONED VOICE. IN THE AURAL PART OF THE EVALUATION. SPECTOGRAPHIC ANALYSIS REVEALS DISSIMILARITIES IN PITCH, RATE OF SPEECH, ACCENT, ARTICULATION, AND PATHOLOGIES. THE VISUAL PART OF THE ANALYSIS GRAPHICALLY DISPLAYS IN THE VOICEPRINT (SPECTROGRAM) THE ACOUSTIC PATTERN OF THE SPEAKER'S VOICE. THE SPECTROGRAPH CONVERTS AN ACOUSTIC SIGNAL RECORDED ON MAGNETIC TAPE INTO A VISUAL PRESENTATION OF TIME VERSUS FREQUENCY, WITH AN INDICATION OF RELATIVE AMPLITUDE. THE CONCLUSIONS DERIVED FROM THESE TESTS TEND TO BE RATHER SUBJECTIVE, HOWEVER, SINCE THEY RELY ON AN EXPERT'S EVALUATION. IN THE PSE, AN INSTRUMENT USES THE HUMAN VOICE AS A MEASURE OF PHYSIOLOGICAL RESPONSE TO PSYCHOLOGICAL STIMULI. NO SENSORS ARE ATTACHED TO THE HUMAN BODY AS IS THE CASE WITH THE POLYGRAPH; ONLY THE VOICE IS USED AS THE BASIC INPUT. DURING A PSE EXAMINATION, A TPAE RECORDING IS MADE OF THE INTERVIEW WITH THE SUBJECT AND THEN PLAYED INTO THE PSYCHOLOGICAL STRESS EVALUATOR. VOLUNTARILY FORMED WORDS CARRY INVOLUNTARY SPEECH COMPONENTS INDICATING STRESS. THE PSE PROVIDES A GRAPHIC READOUT OF THE DEGREE OF STRESS OR NONSTRESS VOICED BY THE SUBJECT DURING THE STRUCTURED LIE DETECTION INTERVIEW. LIKE THE PSE, THE POLYGRAPH RECORDS THE INVOLUNTARY PHYSIOLOGICAL CHANGE TO PSYCHOLOGICAL STRESS. PNEUMATICALLY OPERATED MECHANICAL RECORDERS MEASURE CHANGES IN BLOOD PRESSURE, PULSE RATE AND RESPIRATION; ANOTHER UNIT RECORDS PSYCHOGALVANIC SKIN REFLEX RESPONSE (GSR). CHANGES ARE TRANSMITTED TO A CARDIOSYPHGMOGRAPH PEN AND RECORDED ON A CHART. SUCCESSFUL TESTING DEPENDS ON THE FORMULATION OF TEST QUESTIONS FROM AVAILABLE DATA. THE INVESTIGATIVE AIDS DISCUSSED REQUIRE INTELLIGENT APPLICATION BY A TRAINED EXAMINER; WHEN PROPERLY USED, THEY CAN MAKER WORTHWHILE CONTRIBUTIONS TO LAW ENFORCEMENT AND SECURITY. AND SECURITY.