What is a cold case and how did we get here?

In Episode 2 definitions for “Cold Cases” will be provided along with how the problem  of cold cases has become a crisis.  To accomplish this a piece of research and a historical perspective of homicides during the past decades will be provided. In research conducted by Dr. Jim, he learned from the police agencies who responded to his survey that, 73% of the agencies would declare a case a cold case when there were no more investigative leads; that 20% of them felt that it should be determined bases on the passage of time; while 7% stated that once the original detective had been reassigned or retired, the case would officially then be classified as a cold case.  In actuality it all depends on where you live as each jurisdiction tends to follow different reasoning. As depicted in the below table, one can see that while the number of homicides decreased from 1993 to 2007, the solving of those cases basically remained the same in the 60 percentile range.  So we had about a 40% decrease in the number of homicides with little change in the number solved.  This always begs the question, why?