Mafia don

A crime boss, crime lord, mob boss, kingpin, criminal mastermind, or Don is a person in charge of a criminal organization. A boss typically has absolute or nearly absolute control over his subordinates, is greatly feared by his subordinates for his ruthlessness and willingness to take lives in order to exert his influence, and profits from the criminal endeavors in which his organization engages.

Some groups may only have as little as two ranks (a boss and his soldiers). Other groups have a more complex, structured organization with many ranks, and structure may vary with cultural background. Organized crime enterprises originating in Sicily differ in structure from those in mainland Italy. American groups may be structured differently from their European counterparts, and Latino and African American gangs often have structures that vary from European gangs. The size of the criminal organization is also important, as regional or national gangs have much more complex hierarchies.

The boss in the Sicilian and American Mafia is the head of the crime family and the top decision maker. A boss will typically put up layers of insulation between himself and his men in order to defeat law enforcement efforts to arrest him. Whenever he issues orders, he does so either to his underboss, consigliere or capos. The orders are then passed down the line to the soldiers. This makes it difficult under most circumstances to directly implicate a boss in a crime, since he almost never directly gives orders to the soldiers. Only the boss, underboss or consigliere can initiate an associate into the family, allowing them to become a made man. The boss can promote or demote family members at will. If the boss is incarcerated or incapacitated he places an acting boss who responsible for running the crime family. When a boss dies the crime family members choose a new boss.

The typical structure within the Mafia in Sicily and America is usually as follows:

The term Mr Big is used within the underworld, and within media reportings of persons associated with criminal activities, to refer to a leader of a body of persons functioning in the capacities of roles within organised crime. Sometimes bosses of the so-called gangland are referred to as being Mr Big, as for example in the case of a report of the attempted assassination of an apparent leader of the Irish Republican Army, a person named Alan Ryan. The term implicitly indicates a degree of a possession of a higher intelligence of an individual.

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Wikipedia