Bava Batra 46 - Discovery Request Against a Craftsman
Abaye said to Rava: "Come, and I will show you the practice of the cheats of Pumbedita" (these cheats were craftsmen).
If someone says to one of them, "Give me back my cloak, which I gave you to repair," he answers, "It never happened." And if the claimant persists, "But I have witnesses who saw it in your possession!" - he retorts, "That cloak which they saw was a different one."
And if the claimant says, "Produce the cloak in order to ascertain if it is, in fact, mine," - the craftsman says to him, "I will not produce the cloak because of your unfounded claims, as it would be unfair to the owner."