IN GENERAL, THE COURTS HAVE HELD THAT CONSENT OBTAINED THROUGH DECEPTION, FRAUD, OR MISREPRESENTATION BY LAW OFFICERS IS INVOLUNTARY AND THUS INVALID. SOME COURTS HAVE MAINTAINED, HOWEVER, THAT THERE MUST BE A POSITIVE OR AFFIRMATIVE ACT OF MISREPRESENTATION BY THE OFFICER TO VITIATE THE CONSENT TO SEARCH. THE RECOGNIZED EXCEPTION TO THIS RULE IS IN THE CASE OF UNDERCOVER OPERATIONS IN WHICH THE AGENT ENTERS, NOT BY STEALTH, BUT BY INVITATION UNDER THE GUISE OF FRIENDSHIP OR BECAUSE OF THE MISPLACED CONFIDENCE OF THE WRONGDOER. A MENTALLY INCOMPETENT PERSON IS INCAPABLE OF GRANTING PERMISSION TO SEARCH. IN CASES INVOLVING INTOXICATED DEFENDANTS, THE TEST OF MENTAL COMPETENCE TO CONSENT HAS BEEN USED TO PROVE THE RATIONAL INTELLECT AND FREE WILL OF THE CONSENTER. THUS THE DEGREE OF INTOXICATION IS IMPORTANT. IT IS RECOMMENDED THAT, WHEN THE INDIVIDUAL IS SO INTOXICATED AS NOT TO REALIZE THE NATURE AND CONSEQUENCES OF HIS ACT, THE OFFICER SHOULD ALLOW A PERIOD OF SOBERING-UP BEFORE ATTEMPTING TO OBTAIN CONSENT. THE AGE AND SOPHISTICATION OR EDUCATIONAL BACKGROUND OF DEFENDANTS HAVE BEEN VIEWED AS RELEVANT TO THE VOLUNTARINESS OF THE CONSENT TO SEARCH. CONSENT GIVEN BY YOUNGER AND MORE INEXPERIENCED INDIVIDUALS WILL BE SUBJECT TO GREATER COURT SCRUTINY THAN CONSENT GIVEN BY THE OLDER, HARDENED OFFENDER. THE NUMBER OF OFFICERS INVOLVED IN OBTAINING CONSENT TO SEARCH DOES NOT IN ITSELF INDICATE INVOLUNTARY CONSENT OR COERCION. IN CASES WHERE THE NUMBER OF OFFICERS HAS BEEN AT ISSUE, OTHER AGGRAVATING FACTORS HAVE GENERALLY BEEN INVOLVED, SUCH AS OPEN DISPLAY OF WEAPONS. WHILE AN UNUSUAL TIME OF REQUEST WILL NOT ITSELF INVALIDATE A CONSENT, IT MAY BE A DAMAGING ELEMENT WHEN COMBINED WITH OTHER FACTORS SUGGESTIVE OF COERCION. AS A RULE, CONSENT TO SEARCH SHOULD NOT BE OBTAINED AT NIGHT EXCEPT IN EMERGENCY CIRCUMSTANCES. MISTREATMENT OF A PERSON FROM WHOM CONSENT IS SOUGHT WILL JEOPARDIZE THE VOLUNTARINESS OF CONSENT, AND AN OVERBEARING OR INTIMIDATING ATTITUDE BY THE OFFICER MAY GAIN MERE ACQUIESCENCE WHICH FALLS SHORT OF THE FREE RELINQUISHMENT OF RIGHTS REQUIRED FOR VALID CONSENT. THE WORDING USED IS ALSO IMPORTANT: THE OFFICER SHOULD REQUEST, NOT DEMAND, CONSENT TO SEARCH. IN MOST CASES, COOPERATION IN THE SEARCH BY THE CONSENTING PARTY IS PROOF OF VOLUNTARINESS. THERE IS A CLOSE PARALLEL IN THE LAW BETWEEN CONSENTS AND CONFESSIONS: CIRCUMSTANCES WHICH GIVE RISE TO A COERCED CONFESSION WILL LIKEWISE CAUSE AN INVOLUNTARY CONSENT. FOR PARTS 1-4 AND 6-7, SEE NCJ 48103-48106 AND 48108-48109. (JAP)