Within the mafia, speaking truth is more sacred than the code of silence

Evidence

Unfortunately there is no sure remedy against lies. It is nor surprising, therefore, to learn that when mafiosi address one another, according to all the informants who have turned state’s evidence, the rule is always to speak the truth. The mafioso can choose to remain silent; but if he elects to speak, he must not lie. Lying is supposedly punishable by expulsion and even death, although there is no record of such punishment’s being carried out. The rule of truth is said to be even more important than the notorious rule of silence (VM: 77; TB: I, 126-127 and III, 110; TC: 21). — Diego Gambetta, The Sicilian Mafia The Business of…, 319

Categorization

• XREF: The truth-over-silence rule is the informational substrate that makes Milgrom-style reputation systems workable: private judges and covenants require verifiable (truth-bearing) communication, not just headcounts of who spoke.
• QUESTION: Why is the rule of truth ‘even more important’ than omerta? Could the punishment for lying be a function that is never exercised precisely because its existence is enough to make truth-telling a Schellingian credible commitment?