Forensics in focus

Forensics in focus

Cal State L.A. research team puts sexual assault evidence, cases under the microscope

A team of CSULA faculty and current and former criminalistics graduate students are combing through sexual assault case files to determine how forensic evidence was tested and used. They hope to develop criteria for prioritizing testing and processing in the future. Pictured above are (l-r) Professor and Director of the School of Criminal Justice and Criminalistics Joseph Peterson, Associate Professor Don Johnson, researchers Pui Yee Ada Chan ’09 MS and Froseen Dahdouh ’05, ’06, and project manager Avital Oehler ’07 MS.

In studying criminal justice and forensic science laboratory systems throughout the last 35 years, School of Criminal Justice and Criminalistics Director and Professor Joseph Peterson has worked to ascertain the value of forensic evidence.

Peterson has analyzed the use of forensic evidence in investigations, arrests, case filings, criminal adjudications and sentencing. He has evaluated how evidence is collected, processed and applied.

So, what has he found?

“Forensic science has great potential value but its utility is tempered by many factors, particularly in sexual assault investigations,” Peterson said. “The successful utilization of forensic evidence keys on the decisions of many types of personnel, from crime scenes into the courts, and we have found a great amount of forensic evidence is filtered from the justice process.”

And it is that attrition of evidence in the criminal justice process—propelled, in part, by an overabundance of forensic evidence without the resources to analyze—that Peterson is working to understand and design solutions for addressing. In Peterson’s latest effort, the National Institute of Justice(NIJ)-funded “Sexual Assault Kit Backlog Project,” he has teamed up with faculty colleagues Donald Johnson, Denise Herz and Lisa Graziano, and current and former CSULA graduate students, to look at the use of forensic evidence collected in rape kits for sexual assault cases.

The research team is examining the results of scientific tests performed by private testing laboratories on backlogged sexual assault kit evidence from the Los Angeles Police and Sheriff’s Department crime laboratories to potentially establish criteria for prioritizing evidence testing and build a better understanding of the value of these kits in the future. 

From each file, they are extracting information on the nature, origin and test results of forensic evidence collected from sexual assault victims—particularly the biological evidence that was recovered, the results of DNA testing, and the entry of DNA profiles in large databases.  In addition, the team is determining the investigative and judicial outcomes of a smaller subsample of those cases, comparing the outcomes of cases where the scientific evidence had not been tested with cases where scientific testing was performed, on backlogged as well as nonbacklogged cases.

“This research is very important to me because contemporary knowledge on this subject is largely anecdotal,” said Johnson, who worked as a senior criminalist at the Los Angeles Sheriff’s Department for many years. “Our research will provide empirical data to criminal justice policy makers, crime lab managers, forensic scientists, and other criminal justice professionals to make informed decisions on the investigation and litigation of sexual assault cases.”

The CSULA research project is at the forefront of a national discussion about the value of forensic evidence, and is a supplement to a more comprehensive NIJ study that Peterson, Johnson and Professors Ira Sommers and Deborah Baskin worked on, entitled “Role and Impact of Forensic Evidence in the Criminal Justice Process.” Early analysis from this and other studies have helped fuel debate and legislation—including a bill introduced by U.S. Senator Patrick Leahy—regarding the quality, cost and benefits of such evidence.

Sexual assault kit evidence is a topic that until recently has not gained much traction—especially when the often more sensitive and emotionally-charged features of the cases are taken into consideration, faculty said.

“Despite the popularity of CSI type shows, which stress the value of forensic evidence, there remains a strong need for evaluation of [forensic evidence’s] utility for investigative and prosecution outcomes,” Graziano said.

In doing this study, Peterson noted, the team has been able to seize on the unique opportunity of examining a vast quantity and a variety of sexual assault cases as Los Angeles’ law enforcement agencies process thousands of backlogged rape kits. As private labs contracted by these agencies analyze and review the kits, the CSULA research team gains access to case files to record the testing results and document how the evidence was used.

In the last year, the research team has reviewed and coded about 1,700 randomly selected reports from private testing laboratories. They still have approximately 500 more files to examine, which Peterson said they hope to accomplish by April.

In addition to looking at case files and scientific reports, the team is reviewing criminal justice dispositions in several hundred randomly selected cases and they are conducting focus groups with sexual assault investigators, prosecutors and crime laboratory testing scientists.

“I’ve learned more than I expected,” graduate student and researcher Froseen Dahdouh ’05, ’06 said. “I’ve learned how files are stored, and seen hands-on how the cases are reviewed by other criminalists and administrators to check if the cases have been completed properly, and then I’ve observed the process of the DNA being uploaded and getting CODIS matches to offenders in other cases.”