A criminal justice agency is an "open system," or one that is interactive and responsive to the environment. The management of a criminal justice system is influenced by many factors and groups, including community leaders, community action groups, court decisions, political influences, the media, and individual citizens. For ex, in the 1980's, the U.S. Congress passed mandatory sentencing laws to combat illegal narcotic trafficking. The result was an almost unmanageable increase in the number of inmates incarcerated for drug convictions, creating substantial overcrowding and limiting room for violent offenders.