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Backlog Prevention

There is considerable confusion among journalists and public policy makers about forensic science backlogs, what they mean, and how they can be prevented.  This section is intended to provide a general overview of forensic science backlogs and workloads.


About Forensic Laboratory Workloads

Forensic science laboratories operate in a fashion that is similar to automotive service centers.  Items of evidence (or cars) are brought to a facility with requests for certain kinds of work.  Work is assigned to a technician who completes the work and prepares a report.  In some instances, multiple technicians having different areas of expertise may be assigned to perform different types of work that must also be performed in a certain sequence.  When the work is completed, the customer returns to the facility and takes possession of the evidence (or car).  This is a simplistic model that does not capture the full complexity of work in a forensic science laboratory, but it illustrates accurately how the process generally works.

Forensic science laboratories can track a number of critical indicators to facilitate a comparison of workloads across different time periods.  When the current capacity of laboratories cannot keep pace with demand, the gross backlogs rise proportionately.


Cases and Requests

When a violent crime occurs, evidence is collected at the crime scene and submitted to a forensic science laboratory.  That crime is considered a case and is logged into the laboratory case management system (LCMS).  Multiple work requests, however, may be created for that one case, such as Latent Prints, DNA, and Firearm Identification.  In the laboratory, one violent crime may even have several work requests for the same discipline.  Over the course of a few months, a single violent crime, for example, may have five Latent Print work requests, ten DNA work requests, and six Firearm Identification requests.

During the 2010 fiscal year, the laboratories of the Forensic Science Division provided services in just over 57,000 criminal offenses.  For these 57,000 offenses, 87,800 work requests involving over 97,500 evidence examinations were completed, some of which can take scientists days to finish.   This number includes a count of multiple drug samples identified during the completion of a single work request.


In the simplest terms, a backlog is a count of uncompleted forensic requests in a laboratory or laboratory system.  It is a whole number, such as 950, that represents a snapshot of uncompleted requests.  This may be a backlog count for all uncompleted forensic requests (gross backlog) or perhaps a net count of uncompleted forensic requests for a particular discipline such as DNA or Latent Prints.  Because forensic requests are being created and completed almost on a minute-by-minute basis, backlog counts change constantly.  The net backlog count of cases completed in excess of 30 days tends to be the industry target against which performance is measured.

Although backlogs can be measured with reasonable accuracy, what is actuallyexperienced by criminal justice professionals is just as telling.  Evidence examinations that take several months to complete can cause delays and problems for investigators regardless of what the officially measured backlog may be at any given time.  From a customer service standpoint, what investigators and prosecutors experience is as important as what can be measured – and forensic science professionals must remain sensitive and responsive to both.

In essence, forensic science backlogs are a symptom, not a disease.  It is unacceptable for scientists and managers to become spectators who simply watch backlogs rise.  Furthermore, reactively calling for more people and fiscal resources in the absence of a well coordinated effort to proactively influence backlogs is not appropriate.  A multifaceted approach to preventing backlogs by controlling demand with good management policy and educational outreach must be a constant priority. 


Average Turnaround Time

How backlogs impact the criminal justice system is measured using a different indicator called turnaround time, which is commonly confused with backlog.  Turnaround time is the average period of time that a submitting agency must wait to receive test results after they have submitted the evidence to a laboratory.  Thirty days is widely regarded as an optimum average turnaround time target for a forensic science laboratory.

While backlog counts change minute by minute, average turnaround times tend to remain fairly stable and are therefore a more accurate measure of laboratory progress.  However, turnaround times can be misunderstood as well.

Returning to the scenario where evidence from a violent crime is submitted to one of the Forensic Science Division laboratories, most of the work requests are typically created within a day or two of the initial submission of evidence.  But in many other instances, additional work requests can be assigned to a case over a period of months or even years.  Further complicating the matter, some requests are intentionally delayed when the laboratory has been advised that the police agency will be submitting additional evidence for analysis.  In other words, not all work requests in a laboratory backlog are the result of excessive demand or inadequate capacity.

Expectations and Scope of Work

Forensic science represents an area of public safety investment that pays high returns when scientists apply resources to the analysis of physical evidence that allows the investigation and prosecution of crimes to be performed more accurately and swiftly.  Forensic science professionals carry an unusually heavy burden in this effort.  They are expected to balance the police investigator's – and victim's – wish for fast turnaround of laboratory testing with the legal and judicial expectations of accuracy and completeness.  All the while, it is rarely possible for forensic science personnel to predict if the public significance of a particular case may elevate even after the evidence has left the laboratory.  The expectations of police, prosecutors, defenders, judges, journalists, and victims often conflict, which makes forensic science a demanding and sometimes risky profession.    

Complicating matters, the criminal prosecution of cases is an inherently adversarial process.  Forensic scientists are expected to remain neutral; which is often viewed as frustrating to a party whose interests are perceived as being compromised by the practices and policies of the forensic science laboratory.  Fortunately, good-faith communication and collaboration are usually sufficient to resolve any challenges that arise.  From time to time, however, these efforts fail to produce common ground.  Consequently, forensic science laboratory personnel may be required to exercise professional discretion to ensure that the investment of taxpayer resources delivers the highest possible return of enhanced public safety.

Simply put, the forensic scientist's commitment to due diligence in a case ends with the beginning of the next case waiting to be worked.  Policies that set parameters around what types of evidence will be processed by a forensic science laboratory or what types of analyses will be conducted in the context of given case circumstances have the proven effect of dramatically enhancing the delivery of forensic science services.  The rights of defendants and the interests of victims are protected when forensic testing is timely and accurate.  In the absence of set parameters, or in a system of justice that places no limits on what laboratories are expected to do, experience has demonstrated that laboratories become significantly impaired.

The above graph illustrates how the impact of forensic science services can vary as a function of evidence value from the perspective of both police agencies and prosecutors.  The dark blue area depicted in the Forensic Science Impact Curve represents evidence tested by forensic science laboratories where the results have reasonably high value to the investigation and prosecution of crimes.  The orange area represents lower value evidence where resources would be better directed to higher value activities (opportunity cost).  Forensic science laboratories across the United States, including the FBI Laboratory in Quantico, Virginia, establish evidence submission and analysis policies intended to maximize the impact of available resources while minimizing the opportunity costs associated with evidence testing that routinely produces few benefits for the criminal justice system.  Evidence value often lies in the eyes of the beholder, so there will always be disagreement, in some instances, about what constitutes high value evidence.


The CSI EffectWhat Should be Tested? – 

Forensic science laboratories have a professional and moral obligation to apply their capabilities with due diligence when necessary to support the criminal justice system in determining the following:

  • What crimes were committed
  • The manner in which the crimes were committed
  • The extent of losses, damages, or injuries suffered by victims
  • Who was responsible
  • How to prevent similar crimes from occurring in the future

Problematically, the potential use of forensic evidence in the investigation and adjudication of criminal matters is almost without limit.  For example, forensic scientists could spend several weeks, and exhaust thousands of dollars in consumable supplies, in an attempt to find DNA and fingerprints on a single beer bottle that was thrown onto a person's front lawn by a drive-by litterer.  But it is doubtful that any reasonable criminal justice professional would judge this to be a wise use of resources. This is an extreme example that does not reflect the difficulties associated with evaluating cases that fall in the gray areas.  Ultimately, professional discretion aided by appropriate policies is exercised in the laboratory by qualified and trained personnel.  When a reasonable and appropriately experienced criminal justice professional, armed with the pertinent facts of the case, would consider due diligence to have been exercised by the laboratory, it is then time to move forward with other cases waiting for analysis. 

Many prosecutors have argued that the television show CSI and other programs that dramatize the use of scientific evidence in solving crimes has significantly and unjustifiably inflated the expectations of jurors.  Forensic laboratory testing, as mentioned earlier, is a tool for solving crimes.  It is not and should not, however, be a resource that is abused for the purpose of ruling out every conceivable hypothesis that may arise during the investigation or prosecution of a crime.  This can result in massive crime laboratory delays and forensic scientists who lose motivation and enthusiasm due to the decreasing impact of their work on public safety.  Fortunately, unreasonable demands placed upon laboratories, whether by juries, judges, prosecutors, defenders, or police, can be overcome with effective programs of outreach and communication. 

How forensic science resources are directed to criminal cases cannot be unilaterally dictated by any one party, including the laboratory.  In 2004, the American Prosecutors Research Institute, an affiliate of the National District Attorneys Association, underscored the importance of cooperation in managing forensic evidence:

 In evaluating every case, prosecutors, police and forensic scientists or criminalists should determine what evidence is probative of the defendant's guilt. This evidentiary or case review should be a collaborative process.  

Similarly, Michigan Rule of Evidence 403 allows for the exclusion of relevant evidence on the grounds of prejudice, confusion, or waste of time:

Although relevant, evidence may be excluded if its probative value is substantially outweighed by the danger of unfair prejudice, confusion of the issues, or misleading the jury, or by considerations of undue delay, waste of time, or needless presentation of cumulative evidence.

Scientists are not qualified to make legal interpretations.  But in many instances, it is thescientific nature of the evidence and the generally accepted practices of the relevant scientific community that determine whether or not the analysis of evidence is confusing, misleading, or "a waste of time."  Nor is it uncommon for scientific evidence to be perceived by a prosecutor or defender as being conclusively probative and indicative of a defendant's guilt or innocence when, in fact, prudent scientific practitioners would have a compelling reason to disagree. The unfortunate reality is that these decisions often must be made in the laboratory before cases ever reach the desk of a prosecutor.  For this reason, scientists frequently do their part to keep the criminal justice system as speedy and fair as possible by identifying evidence or analyses that are wasteful or potentially misleading.  When disagreements occur, honest and open discussions with police, prosecutors, and defenders are warranted.


What it all Means

Average turnaround times are the key indicator of progress.  It represents the overall level of service provided by a laboratory as perceived by law enforcement agencies particularly when demand exceeds capacity.  By examining the average output of scientists in particular units over a given time period, projections can be made as to what the optimum level of staffing should be, assuming that effective efforts to eradicate illegitimate demand are being taken.