Information on clients enables blackmail and threat assessment against rivals

Evidence

We need to know about their private affairs not only because they may impinge directly on their economic ones but also for the purpose of blackmail should either party consider cheating the other and thereby us in the process. Even if we protect just one party to a transaction, we still need to know whether the other is harmless, that is, not himself (or himself protected by) someone equally tough or even tougher. — Diego Gambetta, The Sicilian Mafia The Business of…, 94

Categorization

• XREF: Information acquisition here serves both blackmail leverage and competitive intelligence — parallels how a private judge needs to know who else can enforce.