After talking to many investigators who take on the difficult task of investigating cold cases, we discovered some common problems in the way the some of these cases are closed. 

Early on in an investigation, cases are worked very hard.  As leads run out, the investigation starts to lose momentum.  The investigator may be working other cases with more promising leads.  Eventually, the case takes a lower priority and begins to grow cold.  In worst case scenarios, reports are often misplaced or lost, or worse yet, some reports are never completed. 

Some of the common problems encountered are contacts are made and personal information is not documented.  Other information that seems unimportant at the time is not documented and thus never makes it into the case file.  Leads are investigated and not documented.  Years later, when a cold case investigator takes up the case, he or she will waste valuable time reconstructing the investigation.

The cold case investigator should look at the case and start from the beginning.  Re-interview all parties.  Organize the case.  Examine all documentation and evidence.

When closing an unsolved case, consider closing the case so that anyone who later is assigned the case will be able to pick up the case and quickly get organized. 

We recommend that a final case review be done with the unit supervisor.  The supervisor can help insure that any outstanding supplemental reports are submitted to the case file. 

Some issues that will affect the solvability of closed case are records and evidence purging policies and procedures. 

Example:

The homicide has no statute of limitations.  However, the statute of limitations for rape varies from state to state.  Other unsolved rape cases may be related to the unsolved homicide-rape case.  Records and evidence in the homicide-rape case will be maintained.  However, the other rape cases will ultimately be purged.  These purged rape cases could contain evidence and information that could very well solve the cold case homicide-rape case.