Justice/Law Enforcement

Management Summary

Law EnforcementThe main business requirement for this project was to interface a large State Agency’s legacy application to several federal law enforcement systems as well as to the International Justice and Public Safety Network (Nlets).  These federal systems included the National Crime Information Center (NCIC), the Interstate Identification Index (III), and the National Instant Criminal Background Check System (NICS).   Modifications to the State Agency’s existing application were to be kept to a minimum.  As expected, security was of utmost importance.


  • Law Enforcement relies on the Nlets network for the communication of law enforcement-related messages between States.
  • Law Enforcement relies on the NCIC network for access to federal law enforcement-related databases.
  • Both communicate directly with State-level computing systems, which, in turn, communicate with local agencies.
  • Some mainframe-based State-level computing systems operate on legacy mainframes that do not easily support the communications protocols required by Nlets and NCIC.

Business Objective

  • Hide all technical interface complexities from existing back-end applications

Functional Requirements

  • Support Hot File requests (stolen vehicles, wanted persons, missing persons) to the NCIC database
  • Support III requests routed through NCIC
  • Support III responses returned by Nlets
  • Support National Instant Criminal Background Checks by firearms sellers routed to NCIC
  • Support interstate queries and messaging such as:
    • Driver’s license queries
    • Vehicle queries
    • LoJack® stolen vehicle recovery system notifications
    • AMBER alerts
    • Stolen vehicle feed from NCIC
  • Recognize messages indicating when Hot Files, III, and NICS statuses change (online/offline)
    • Delay message submission when offline
    • Submit delayed messages when online
  • Provide ultra high availability—messages include information that impacts the safety of law enforcement officers in the field

Technical Requirements

  • Provide interfaces to Nlets and NCIC using IBM WebSphere® MQ
  • Support asynchronous and synchronous request/response handling
  • Provide reliable delivery of asynchronous messages
  • Audit all message transmissions as required by law


By the development of a number of Filters, the Plexus Message Broker was enhanced to provide the necessary interfaces to Nlets, NCIC, III, and NICS.  Automatic starting/stopping of message routing to NCIC and NICS was automatically sensed and handled.  Furthermore, the complexity of interfacing to these systems was kept hidden from the back-end application systems.