Forensic laboratories need the irrefutable integrity of a LIMS to track evidence testing and handling

With the addition of DNA profiling to the forensic scientist's toolkit, the ability to analyze clues at the molecular level has enabled the lab to be even more definitive about results. However, the introduction of DNA analyses into the courtroom has sparked corresponding questions from the defense about the manner in which the evidence has been handled. Not only is the chain of custody scrutinized, but the techniques and procedures that were performed also come under examination.

THE EVIDENCE TRAIL
Criminal evidence needs to be tracked from collection through disposition. Chain of custody is often pivotal to the outcome of a prosecution and must be legally and properly processed. This process involves not only carefully handling evidence, but thoroughly documenting its movement from one pair of hands to the next. It is made more difficult when the number of people involved in a crime investigation increases. In addition, sometimes the forensic specialist is not the person who collects the evidence, and not all evidence is sent to the lab. Finally, the detailed tracking of individual case information becomes ever more difficult as overall caseloads continue to increase, with little or no corresponding increase in the number of forensic lab workers.

Managing the movement of evidence...

The sensational murder trial of O. J. Simpson is having a long-term impact on how evidence is managed. Indeed, it has become clear that the evidence trail is equally as important as the evidence itself. In that trial, the DNA analyses were conclusive, proving that Simpson's blood and the blood of the two victims were together in several places and on several items from the crime scene.

The results of DNA tests performed on key items of physical evidence collected in the case, including blood, hair, and fibers, were introduced as evidence. Each item of physical evidence was handled by at least three people from the time it was collected to the time it was tested. During the trial, the chain of custody needed to show that it was "reasonably certain" that each item tested by the laboratory was the same item that was originally collected.

Simpson's defense claimed that the evidence had been planted, causing the manner of collecting, storing, processing, and testing of all forensic evidence to be examined in minute detail. The subsequent investigation unearthed numerous inconsistencies. Photographs and videos of the crime scene did not always corroborate with verbal testimony. Photographs did not show items and blood stains in places where they were reported to have been, and videos did not always match still photos. In addition, the presence of the blood preservative EDTA in some of the bloodstains came under question. In the end, the inability to provide a seamless chain of custody and unquestionable evidence severely damaged the prosecution's case.

"The O. J. Simpson trial illustrated the exposure a law enforcement agency had to criticism of their findings," explains Peter Ciccotelli, senior account manager of LabVantage Solutions (Secaucus, NJ). "The questions of how easy it was to misplace samples, to process evidence incorrectly, to `break' the internal chain of custody, [and] to delay testing of critical evidence to the point of it being invalid were asked. All of a sudden, the forensic unit of the police agency was receiving more than its share of scrutiny."

In cases such as the Simpson trial in which hundreds of pieces of evidence are handled and stored for months, computerizing the case history information is the only answer that can conclusively support the integrity of the chain of custody. Using a laboratory information management system (LIMS) greatly simplifies information handling and documentation. Because a LIMS can track large amounts of evidence and case-related information across various sections of the laboratory, and even across networked laboratory systems that span large geographical areas, it is ideal for forensic laboratories. In addition, because a LIMS uses bar coding and password security, when the integrity of an evidence trail is challenged in court, the records maintained by the LIMS can show who handled the evidence, how and when it was transferred to another person or location, and who examined it.

THE CONNECTED CRIME LAB
"While the crime lab is still a lab, there are differences," Ciccotelli observes. "A single piece of evidence may be transferred from department to department for tests depending on the nature and type of case. That same type of evidence, submitted to the lab for another case, may never need to get tested. Methods of reporting and the type of data captured differ from department to department as well. The questions asked and the amount of information obtained about submitted evidence are determined by the lab section performing the tests."

FIGURE 1. Typical flow diagram:

Not only do reporting methods differ, but so do the type and volume of reports. According to E. H. Foerster, senior toxicologist for The Institute of Forensic Science at the University of Texas-Dallas, "Some specimens require two or three reports to be returned to the submitting agency from each department, although usually only a single report from toxicology is expected." The submitting agency differs for the specimens as well and can vary among the police department, the medical examiner, or a hospital depending on the specimen and the case type.

Forensic laboratories are different in other ways as well. Most striking is the perspective concerning the significance of particular evidence. All evidence from a crime falls under the umbrella of a single case, prompting the forensic analyst to look at the evidence collectively rather than individually. Indeed, a single piece of evidence may have no significance without the support of other evidence. And because the forensic analyst develops conclusions based on the evidence, it may not be necessary to test every item to draw those conclusions, even though several items of evidence may be submitted by the police agency to the lab. The level of testing is sometimes determined by the type of case; that is, a homicide may require that extensive testing be done on everything submitted, whereas a lesser crime may not. The final report is for the case, not an individual item. This approach is at odds with the typical commercial or research laboratory that tests every sample religiously. All case evidence, however, must be included in the chain-of-custody audit trails.

"The chain of custody is a very serious aspect," Foerster emphasizes. "Some labs have such vigorous chain-of-custody procedures that a separate person stores the specimen so that the analyst doesn't even get the original specimen bottle, just the sample," he says. A forensic LIMS, therefore, must accommodate the special needs of the crime laboratory, from handling the variety of sample types to complying with intensive chain-of-custody requirements.

Ciccotelli points out that "because a crime lab looks at all the evidence submitted for the case, not one item at a time, this `case-level' approach is where most commercial LIMS could not survive. A typical LIMS is designed to track items at a sample level, and it is cumbersome to organize these items under the umbrella of a single case. In addition, some crime labs do more investigation than others." He adds, "They need a LIMS to provide `investigative tools' and built-in queries that identify associations and possible relationships between case-related information such as suspects, case types, and results."

"Finally, a typical commercial LIMS has trouble because not all the evidence, or samples, are analyzed. Normally, if you submit a sample, you test it and report an individual result. To say that we will submit fifteen pieces of evidence and only test eight is contrary to the normal LIMS rules," states Ciccotelli.

There are three forensic LIMS on the market, all of which feature powerful chain-of-custody tracking capabilities. LabVantage Solutions' TRACE (tracking reporting and analysis of criminal evidence) accommodates all types of cases at all stages of an investigation and allows users to attach audio and video files (Figure 1). AG Communication Systems' (Phoenix, AZ) JusticeTrax LIMS-plus emphasizes caseload management tools and the reporting requirements of different laboratory sections. Porter Lee's (Lake Zurich, IL) Crime Fighter BEAST (barcoded evidence analysis statistics and tracking) LIMS automates the chain of custody by using bar coding to track samples. In addition, L.I.M.S. USA (Hollywood, FL) and Quality Systems International (Wyckoff, NJ) offer forensic modules for their LIMS.

Ideally, the LIMS should not only be the repository for evidence data and crime scene data, but should also provide access to court records, arrest information, inter- and intralab analyses, medical reports, electronic recordings and scanned documents, other internal agency computerized databases, interrogations, surveillance, and more. As has been pointed out, the dilemma lies not in the ability of the forensic lab to accurately analyze evidence and samples, but in the issues surrounding how to accurately accommodate the various people handling samples and the legal requirements for sample handling and tracking. These issues have been a burden for quite some time because reduced funding has limited the number of forensic staff while legal demands have increased the need for irrefutable evidence integrity. They came to international attention with the O. J. Simpson trial and will continue to affect forensic labs and their information management methodology in the years to come.

THE FUTURE FORENSIC LAB
Several social and technological trends are converging that will profoundly change the forensic laboratory. Already, computer crimes are opening up a new area of criminal investigation that is becoming incorporated into lab methodology. The new breed of forensic computer experts will fall under the heading of behavioral specialists and will work closely with forensic psychologists in pursuit of the computer criminal.

It is expected that the microscope will be partly replaced in the future with three-dimensional laser scanning equipment, such as a laser profilometry system. Currently, laser profilometry is slow and there are artifacts in the scanning. But these problems will be resolved, and the equipment will become faster and more accurate.

Open database connectivity technology is now providing access to a wide range of database technologies, such as neural networks and pattern recognition databases, which are being used to analyze shoe prints and toolmarks. Soon, data-mining tools will have a significant impact. These new computer-aided analysis tools can link and chart case information, allowing the investigator to question the data and pose scenarios as well as suggest and follow possible investigative paths. As a result, connections that often took weeks or months to come to light are revealed in a fraction of the time.

Funding will be as much an issue in the future as it is today. All the exciting tools in the world won't do much good for the department that can't afford to buy them. However, this may become a moot point; as a result of the attention now being paid to evidence integrity and analytical methodology, forensic labs may be forced to find new sources of monies or to outsource analytical tasks. Because of this, the day when an industry-wide standard that dictates testing criteria and methodologies becomes required by law is not far off.

The industry is currently self-regulated, although adherence to various standards is not consistently applied. Whereas forensic DNA testing laboratories follow the DNA Advisory Board's quality assurance standards, other forensic labs do not have such an obvious leader. "Unlike some industries, there is no overseeing organization to determine how testing gets done or even if they need to use a LIMS," Ciccotelli remarks. "The American Society of Crime Laboratory Directors (ASCLD) suggests ways of doing business in a crime lab, mainly covering general procedures. ASCLD will inspect the lab, documentation, and procedures to ensure consistency and conformity to its standards. The lab can then be classified as ASCLD-certified, which is becoming increasingly important. However, ASCLD will not validate a LIMS or the company that supplies it." Some states already require by law that all crime labs must be ASCLD-certified by a specific date or they forfeit their rights to accept additional work. Given the direction that the industry and various states are taking, standards will soon be universally implemented and the ASCLD will no doubt take a more active role in the future.

"Forensics is just beginning to get looked at," Foerster notes. "Right now the problems are cost and that government is slow to adopt new technology. One of these days everyone will have a LIMS."