WHENEVER OBJECTS OR PERSONS COME INTO CONTACT A TRANSFER OF MATERIALS INVARIABLY RESULTS. EVERY CRIMINAL ACT THEREFORE RESULTS IN SUCH TRANSFER OR ALTERATION WHICH MAY THEORETICALLY BE USED TO CONNECT A SUSPECT WITH THE CRIME. THE MOST PRODUCTIVE SOURCE OF PHYSICAL EVIDENCE IS USUALLY THE CRIME SCENE ITSELF. MATERIAL FOUND AT OR NEAR THE SITE MAY AID IN CLARIFYING WHAT OCCURRED AND IN IDENTIFYING THE PERPETRATOR. THE SUSPECT, HIS RESIDENCE, AND VEHICLE ARE OTHER MAJOR SOURCES OF PHYSICAL EVIDENCE. THE ULTIMATE VALUE OF PHYSICAL EVIDENCE IS ITS ADMISSIBILITY IN COURT. BEFORE EVIDENCE CAN BE ADMITTED IN COURT, AUTHENTICATION WILL BE REQUIRED. THIS IS USUALLY ACCOMPLISHED BY A WITNESS, OFTEN A POLICE OFFICER, WHO IS AWARE OF THE CONNECTION BETWEEN THE OBJECT AND THE CRIME. EVIDENCE, TO BE OF VALUE, CAN NOT BE TAMPERED WITH OR CONTAMINATED. THIS REQUIRES THAT THE CHAIN OF POSSESSION BE MAINTAINED. THE CHAIN OF POSSESSION BEGINS WHEN AN OFFICER DISCOVERS OR OTHERWISE GAINS POSSESSION OF THE EVIDENCE. THE OFFICER WHO HAS CHARGE OF THE EVIDENCE MUST BE ABLE TO ACCOUNT FOR EVERY MINUTE THAT THE EVIDENCE IS IN HIS OR SOMEONE ELSE'S POSSESSION. THE FEWER PEOPLE HANDLING THE EVIDENCE, THE LESS CHANCE THAT EVIDENCE MIGHT BE LOST OR ALTERED. THE BURDEN OF PROOF FOR THE VALIDITY OF THE EVIDENCE IS ON THE PARTY OFFERING THE OBJECT IN EVIDENCE. RECORDING THE EVIDENCE WILL REQUIRE PHOTOGRAPHS OF THE EVIDENCE AT THE SCENE OF THE CRIME. EVIDENCE SHOULD BE MARKED FOR IDENTIFICATION WITH THE OFFICER'S INITIALS, THE TIME, DATE, AND CASE NUMBER. IF THE EVIDENCE IS SURRENDERED TO ANOTHER, THIS SHOULD ALSO BE RECORDED. EACH POLICE DEPARTMENT SHOULD HAVE A ROOM FOR STORAGE OF PHYSICAL EVIDENCE. LOCATION OF THE EVIDENCE IN STORAGE SHOULD ALSO BE RECORDED, AND THE ROOM SHOULD BE KEPT LOCKED. THE EVIDENCE ROOM SHOULD HAVE A RECORDS SYSTEM WHICH REFLECTS THE LOCATION, DATE OF RECEIPT AND RELEASE OF EVIDENCE, CHARACTER AND TYPE OF EVIDENCE, THE CHAIN OF POSSESSION, AND THE DATE AND RESULTS OF ANY INSPECTIONS OF EVIDENCE OR AUDITS OF THE RECORD. BEFORE EVIDENCE IS REMOVED FROM STORAGE, THE IDENTIFICATION OF THE RECIPIENT, REASON FOR REMOVAL REQUEST, AND REASON FOR AND AUTHORIZATION OF REMOVAL SHOULD BE REQUIRED. EVIDENCE SHOULD BE TRANSPORTED IN A DROP BOX, A LOCKED, HEAVY DUTY CONTAINER WITH AN APERTURE PERMITTING DEPOSIT OF THE EVIDENCE. IF EVIDENCE IS MAILED, THE PACKAGE SHOULD BE CAREFULLY WRAPPED AND ADDRESSED AND SENT BY REGISTERED OR CERTIFIED MAIL. PROPER DISPLAY OF THE EVIDENCE IN COURT IS ALSO IMPORTANT. ONCE EVIDENCE HAS SERVED ITS PURPOSE IT SHOULD BE RELEASED AND PROPERLY DISPOSED OF OR DESTROYED. DISCUSSION QUESTIONS BASED ON THE ABOVE INFORMATION ARE ALSO PROVIDED. (JAP)