JUDGES AND PROSECUTING ATTORNEYS ARE FREQUENTLY DISAPPOINTED WITH POLICE WITNESSES BECAUSE BEGINNING OFFICERS ARE INEXPERIENCED WITH COURT PROCEDURES AND BECAUSE JUSTICE OFFICIALS HAVE PRECONCEIVED NOTIONS ABOUT THE POLICE. DIFFICULTIES ARISE FROM THE DOUBLE FUNCTION OF THE POLICE AS INVESTIGATORS AND PROTECTORS, FOR THE POLICE METHOD OF ANALYSIS AND INVESTIGATION CANNOT ALWAYS SATISFY THE EVIDENCE REQUIREMENTS OF THE COURT SYSTEM, UNLESS OFFICERS ARE THOROUGHLY FAMILIAR WITH COURT PROCEDURES. PARTICULARLY PROBLEMATIC CRIMES INCLUDE THE FOLLOWING: (1) COMMON CRIMES (TRAFFIC VIOLATIONS AND ACCIDENTS, AND ROBBERY) IN WHICH DETAILS ARE SIMILAR AND SIMULTANEOUS NEED FOR INVESTIGATIVE AND PROTECTIVE FUNCTIONS MAY DIVERT OFFICERS' ATTENTION FROM IMMEDIATE EVENTS; (2) LARGE-SCALE PROCEEDINGS CONDUCTED BY THE COURT AND REQUIRING CAREFUL SELECTION OF WITNESSES BECAUSE POLICE CAN ONLY MAKE LIMITED STATEMENTS WITHOUT CONNECTION TO THE BROAD CONTEXT; AND (3) PROCEEDINGS WITH AN AGGRESSIVE DEFENSE STRATEGY WHICH UNNERVES POLICE OFFICERS BY PLACING THEM IN A DEFENSIVE POSITION AS REPRESENTATIVES OF A CORRUPT SYSTEM AND WHICH CAN ONLY BE COUNTERACTED WITH VIGOROUS OBJECTIONS FROM THE PROSECUTING ATTORNEY. REGULATIONS PROTECTING THE RIGHTS OF POLICE WITNESSES, PARTICULARLY IN THE THIRD SITUATION ABOVE, ARE NEEDED TO PREVENT DISTORTION OF FACTS. QUALIFIED EXPERT POLICE WITNESSES ARE ESSENTIAL FOR TESTIMONY IN TECHNICAL MATTERS, BUT EVEN THOUGH SUCH PERSONS ARE NOT IMMEDIATELY INVOLVED IN INVESTIGATIVE PROCEDURES, THEIR OBJECTIVITY IS FREQUENTLY QUESTIONED BECAUSE OF THEIR POLICE AFFILIATION. THEIR EXPERTISE MUST THEREFORE BE SATISFACTORILY ESTABLISHED. -- IN GERMAN. (KMD)