Stephen J. Niezgoda Jr. and Barry Brown Ph.D.
Federal Bureau of Investigation
On a Friday afternoon in March 1989, Debbie Smith, whose husband, Robert, is a police officer, was abducted from her home by a man she had never seen before. Mrs. Smith's assailant forced her from her kitchen to the woods behind her home. He proceeded to rape her. Before leaving the scene of the crime, the rapist threatened Mrs. Smith, saying he knew where she lived and he would kill her if she ever told anyone what had happened.
The local police department developed a suspect in the case, and sent a sample of his blood, along with the evidence, to their forensic crime laboratory. A conventional serology exam excluded the suspect. However the examiner instructed the investigating officer to preserve the evidence; there was a new examination based on DNA that could possibly solve this crime sometime in the future.
Five years later, in 1994, the county where Debbie and Robert Smith resided experienced an outbreak of sexual assault and rape crimes. The police developed a suspect in this case, and sent a sample of his blood to the laboratory. The police also resubmitted the evidence from Debbie Smith's case, thinking the same subject may be responsible. This time, the laboratory performed DNA analysis. Again, the suspect was excluded. But now, the laboratory had developed a DNA profile of the man who raped Mrs. Smith.
Meanwhile, in the years since the assault on Debbie Smith, the state had undertaken developing a databank containing DNA profiles from convicted felons. As the examiners developed convicted offender profiles, they periodically searched them against unsolved cases. This summer, Debbie Smith's rapist was identified from a match against this databank. The criminal, Norman Jimmerman, was already incarcerated for abduction and robbery. He is currently serving a 161 year sentence. The District Attorney has decided to prosecute the case; Mr. Jimmerman is a two time felon and the rape of Debbie Smith will be his third strike. When informed that the man who raped her had been identified, Debbie Smith said, "I feel like a weight has been lifted from my shoulders."
This is a true story. The hit was made at the Virginia Department of Forensic Services crime laboratory, in Richmond, Virginia.
The COmbined DNA Index System, CODIS, blends computer and DNA technologies into an effective tool for fighting violent crime. The current version of CODIS uses two indexes to generate investigative leads in crimes where biological evidence is recovered from the crime scene. The Convicted Offender index contains DNA profiles of individuals convicted of felony sex offenses (and other violent crimes). The Forensic index contains DNA profiles developed from crime scene evidence. CODIS utilizes computer software to automatically search these indexes for matching DNA profiles.
The word "index" in COmbined DNA Index Systems is not arbitrary. CODIS is a system of pointers; the database only contains information necessary for making matches. Profiles stored in CODIS contain a specimen identifier, the sponsoring laboratory's identifier, the initials (or name) of DNA personnel associated with the analysis, and the actual DNA characteristics. CODIS does not store criminal history information, case-related information, social security numbers or dates-of-birth. Matches made among profiles in the Forensic Index can link crime scenes together; possibly identifying serial offenders. Based on a match, police can coordinate separate investigations, and share leads developed independently. Matches made between the Forensic and Convicted Offender indexes ultimately provide investigators with the identity of the suspect(s).
CODIS also supports a Population file. The Population file is a database of anonymous DNA profiles used to determine the statistical significance of a match.
CODIS is designed so that forensic laboratories have control over their own data. The system has three tiers (or levels): local, state, and national (fig. 1). The forensic and convicted offender indexes, and the population file may exist at each tier.
Typically, the Local DNA Index System, or LDIS, is installed at crime laboratories operated by police departments, sheriff's offices, or state police agencies. At the local level, DNA examiners use CODIS software on the bench when sizing autoradiograms. After sizing, examiners transfer unknown subject profiles into the local forensic index, where they are searched against other unkown subject profiles. The custodian of the local database can share this data with other CODIS labs within the state by forwarding it to the state level.
Each state participating in the CODIS program has a single State DNA Index System (SDIS). The SDIS is typically operated by the agency responsible for implementing the state's convicted offender statute. At the state level, inter-laboratory searching occurs. That is, the DNA profiles submitted by different laboratories within the state are compared against each other. Forensic profiles developed at local laboratories are also searched against the Convicted Offender index. The state custodian can share this data with the rest of the CODIS community by forwarding it to the national level.
The National DNA Index System, or NDIS, is operated by the FBI. NDIS provides a mechanism for forensic crime laboratories located throughout the United States to share and exchange DNA profiles. The DNA Identification Act of 1994 formalized the FBI's authority to establish a national DNA index for law enforcement purposes.
Today, forty states have passed legislation requiring convicted offenders to provide biological samples for DNA databasing (fig. 2). These statutes cover over 90% of the U.S. population. There are differences among state laws, but all cover felony sex offenses. Eight states have passed legislation this year, and three states have pending legislation. In addition, the FBI is in the process of drafting a federal DNA database law, covering federal and military courts and the District of Columbia.
According to an FBI Laboratory survey of 132 crime laboratories conducted in Summer 1995, twenty-three states are collecting convicted offender samples. The top five states, Virginia, Washington, California, North Carolina and Alabama account for over 80% of the 250,000 samples collected. Nineteen laboratories are currently analyzing offender specimens. As of this summer, approximately 50,000 samples have been analyzed; 47,000 with RFLP and 3000 with PCR. The bulk of the PCR data has been generated by Alabama. Eleven states plan to begin collecting and/or analyzing offender samples within the next eighteen months. Analyzing the high volume of convicted offender samples requires significant resources. To compensate, most states prioritize the analysis of convicted offenders by type of offense and release date.
CODIS began as a pilot project in 1990, serving fourteen state and local DNA laboratories. Today, CODIS is installed in forty-two laboratories in twenty-two states and the District of Columbia. The FBI provides CODIS software, together with installation, training, and user support, free of charge to any state and local law enforcement laboratories performing DNA analysis. Each laboratory is responsible for purchasing all hardware and commercial-off-the-shelf software necessary to operate CODIS. Commercial hardware and software include IBM PC compatible computers, MS-DOS, Windows and Windows NT, database management system software, and communications software.
CODIS version 4.3, scheduled for release in October 1995, fully implements the forensic and convicted offender indexes at the local, state and national levels. CODIS Version 4.3 supports both the RFLP and the PCR DNA analysis methods. Specifically, the software contains the following features:
The FBI offers a one-week CODIS training course to DNA analysts from participating laboratories. For new labs, the FBI visits the laboratory, installs the software, and presents a one day training seminar. Approximately ninety forensic examiners throughout the US have received CODIS training to date. The FBI also provides end-user documentation consisting of the CODIS Functions Guide and the CODIS Training Reference Manual.
The FBI also operates a Help Desk for CODIS users between the hours of 8:00 AM and 5:00 PM Eastern. In 1995, the CODIS Help Desk services approximately 100 calls per month.
The FBI measures the success of the CODIS program by counting the crimes it helps solve. Our metric, the "cold hit", is defined as a match which provides the police with an investigative lead that would not otherwise have been developed. In other words, CODIS cold hits are unexpected!
There are two ways to count hits-by subject and by victim. One subject may be responsible for several crimes, each involving at least one victim. CODIS has produced a total of twenty-eight case-to-case hits (i.e., matches within the forensic index) (fig. 3). These twenty-five criminals have victimized seventy-nine individuals. There have been twenty-five case-to-offender cold hits (i.e., matches between the forensic and offender indexes) (fig. 4). The following two examples illustrate typical CODIS hits.
St. Paul Minnesota, November 1994: A man wearing a nylon stocking over his face and armed with a knife jumped out from behind bushes and forced a woman who was walking by to perform oral sex. Semen recovered from the victim's skirt and saliva was analyzed using DNA technology. The resulting profile was searched against Minnesota's CODIS database. The search identified Terry Lee Anderson, who confessed and is now in prison.
Tallahassee Florida, February 1995: The Florida Department of Law Enforcement linked semen found on a Jane Doe rape-homicide victim to a convicted offender's DNA profile. The suspect's DNA was collected, analyzed, and stored in a CODIS database while he was incarcerated for another rape. The match was timely; it prevented the suspect/offender's release on parole scheduled eight days later.
The laboratories which have experienced success with CODIS share one characteristic-they all have policies for working unknown subject cases. The primary purpose of CODIS is to help solve crimes in which there are no suspects.
Following are the major enhancements planned for CODIS for Fiscal Years 1996 through 1998:
The FBI Laboratory intends to activate the National DNA Index System (NDIS) in the Fall of 1995. NDIS will allow crime laboratories located in different states to compare and exchange DNA profiles. When NDIS is activated, there will be approximately 50,000 convicted offender profiles and 10,000 forensic profiles available for uploading and searching. Based on surveys of state and local crime laboratories, the FBI anticipates the number of profiles stored in NDIS to increase to approximately 250,000 by the end of 1997. The capacity of the current version of NDIS is insufficient to handle this high transaction volume. The FBI will redesign the LDIS, SDIS and NDIS so they share a common design for DNA Indexes and network communications, optimized for performance.
The Unidentified Persons index will contain DNA profiles of persons whose identities are sought by investigators. Examples include: small children recovered by police who are unable to provide information concerning their identities; juvenile runaways who intentionally seek to conceal their identities; John and Jane Doe murder victims; and unidentified body parts. DNA profiles in the Unidentified Persons Reference index will be searched against profiles in the Unidentified Persons index to determine identity. This index will contain DNA profiles from missing persons (e.g., hair from a hairbrush, genetic material provided for medical purposes) and DNA profiles voluntarily submitted by close biological relatives of missing persons.
The Victim index will contain DNA profiles voluntarily provided by victims of violent crimes that were not cleared by arrest. When criminals leave a crime scene, they often transport genetic material from the victim. (For example, a victim's blood might spatter on the criminal's shirt.) Comparing the Victim and Forensic indexes could generate investigative leads in these cases.
The FBI is in the process of implementing a high performance network backbone to support the DrugFire program. This backbone, known as LABNET, will link crime laboratories throughout the country via a high bandwidth wide area network (WAN). During 1997, the FBI will port the CODIS communications subsystem to LABNET.
The CODIS installed base will triple over the next several years, for two reasons. First, the rapid increase in states with convicted offender statutes is creating a demand for CODIS software. As of July 1995, forty states have passed legislation requiring convicted offenders to provide sample (blood, saliva, etc.) for DNA profiling (fig. 5). Twenty-three states have already begun collecting these samples. Approximately eleven more states will start collecting and analyzing samples by January 1997. Laboratories in these states need CODIS software to share their data with the rest of the country. Second, the number of crime laboratories performing DNA analysis is steadily increasing due to DNA's effectiveness as a forensic tool. Of the 200 crime laboratories in the US performing serology examinations, 90 are already using DNA. At least 16 laboratories plan to start DNA programs in the near future. More serology labs will convert to DNA as the technology barriers fall and prices decrease. All of these new DNA laboratories are potential CODIS customers.
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