The kidnap prohibition may have emerged from an internal factional exploit.

Evidence

A further circumstantial motivation was raised by the judges, who suggested that the prohibition came about because Toto Riina and Pippo Calò joined forces to kidnap the adult son of Cassina in 1972, taking advantage of the fact that Stefano Bontade and Gaetano Badalamenti, Cassina’s protectors, were both in prison (OSPA : V, 907). — Diego Gambetta, The Sicilian Mafia The Business of…, 455

Categorization

• QUESTION: If the anti-kidnaping rule originated as a factional attack on rivals’ clients, then the rule-serving-norms narrative is partly a rationalization of power politics — worth investigating whether Gambetta addresses this.
• XREF: Kidnaping rivals’ protected clients as a weapon against competitors mirrors the ‘entering the territory of another protection firm’ dynamic from the earlier chapters.