This thesis investigates the frequency of use and perceptions of usefulness of federal criminal justice information systems among state and local law enforcement personnel and certain IS environmental factors that affect usage. The study is predicated by a demonstrated need for increased information sharing, interoperability, and collaboration among the three tiers of law enforcement as public safety threats within U.S. borders increase in complexity; e.g., the Murrah Federal Building bombing, Columbine High School shooting, 9/11 terrorist attacks, and D.C. sniper case. The results of this research indicate high usage and perceived usefulness of the National Crime Information Center Network (NCIC Net), National Law Enforcement Telecommunications System (NLETS), Uniform Crime Reporting/National Incident Based Reporting System (UCR/NIBRS), National Instant Criminal Background Check System (NICS), and federal LE websites. The results also indicated that the IS environmental factors information quality and trust influenced the usage and perceived usefulness of federal criminal justice information systems.