Recent advancements in DNA technology have improved law enforcement's ability to use DNA to solve old cases. Newer DNA analysis techniques can yield results from small samples of biological evidence invisible to the eye. The usefulness of DNA evidence depends upon the maintenance of an ever-expanding database of DNA information to which DNA evidence from new and old crimes can be compared. States and the FBI store hundreds of thousands of potential suspect DNA profiles in convicted-offender DNA databases. A computer software system called CODIS operates local, State, and national databases of DNA profiles of convicted offenders, unsolved crime-scene evidence, and missing persons. Newer DNA technologies, broader offender DNA collection statutes, and forensic casework demands have created a backlog of DNA samples waiting to be analyzed. It is estimated that there are between 500,000 and 1,000,000 convicted offenders whose DNA samples remain to be collected. Prisons and jails throughout the country are a critical component of the Nation's DNA database system. The vast majority of DNA sample collections are managed by corrections departments, jails, and juvenile facilities. President Bush has called on Congress to fund a 5-year DNA initiative intended to eliminate both convicted-offender and forensic investigative DNA backlogs.