The Signori di notte (Lords of the night) were magistrates primarily responsible for security in the city at night. They were six, one for each sestiere.
“Esecutori contro la Bestemmia” from the Lessico Veneto (1851) by Fabio Mutinelli, translated by René Seindal.
In ancient Venice prostitution was considered a necessary evil, where more harm would come from a ban than from a de facto acceptance