Venice at the height of its power conjures images of merchant traders, carnival masks and debauchery. But for all its decadence Venetian life was governed by a well-established democracy with strict standards of behavior that held society together.

The State empowered citizens to police each other and even encouraged them to denounce unlawful misconduct via a network of bocche di leone, or lion’s mouths, post boxes. And despite sounding like an invitation for backstabbing, slander and malicious gossip, it arguably worked well. Here’s what you need to know before posting your accusation.