The answer is the second option: Master Hauchecorne, who is often deceitful, breaks down when people don't believe he is telling the truth.
The short story "The Piece of String", by Guy de Maupassant, revolves around the irony stated in the sentence above.
The main character, Master Hauchecorne, is accused of having found a pocket book containing some money inside it and is asked to return it. In reality, he has not found the pocket book, but a mere piece of string that he decided to pick up because he belives anything can be valuable if there is some use to it later on. While picking the string up, he's watched by an enemy of his, who becomes his accuser in the future.
Master Hauchercorne is a peasant, but a greedy one. His greediness is precisely what causes him trouble. Had he not decided to pick up such an unimportant object as the string, he would not have been accused of anything at all. When the truth is finally out and the pocket book is returned by someone else, people have a hard time believing Master Hauchecorne was innocent all along. His personality is well known by everyone. And he admits it himself that he would be capable of doing such a thing as picking the pocket book from the floor, in case he had had the chance:
He went home indignant, choking with rage, with confusion, the more cast down since with his Norman craftiness he was, perhaps, capable of having done what they accused him of and even of boasting of it as a good trick.