Rabbah bar Bar Chanah lost a Get in the Beis Medrash, he said "I can either give a Siman(sign of authentication) or, I can recognize the Get" and they returned it to him. He replied I do not know if they returned it to me because of my Siman, and they hold that Simanim work mid'Oraisa, or because I recognized it and specifically a "tzurba m'drabanan" a rabbinical scholar is believed to say that he recognizes his lost Get, however a commoner is not believed. Tosofos explain we don't return it to a commoner because they lack trustworthiness.
We should all strive to be like a "tzurba m'drabanan " and try to ensure that we have a reputation of scrupulous honesty. There is a story with a lawyer who once called the Chofetz Chaim as a character witness and told the following story of the Chofetz Chaim's character to the judge:
Once, when the Chofetz Chaim was in Warsaw, he was approached by a man with a five ruble note in his hands, who claimed that he owed the Chofetz Chaim a ruble for a book he had once bought from him. The Chofetz Chaim refused the money, saying that he did not remember such a debt, and it would be better to approach his accountant, who might have a record of the debt. After receiving this reply, the man changed his tune, this time claiming that he wanted to give a ruble as a donation. The Chofetz Chaim said he did not accept presents, but if he so wished, he could donate the money to the yeshivah in Radin. The person agreed to do that, but when the Chofetz Chaim took out his wallet to give him change, he grabbed the wallet and ran away. The Chofetz Chaim began to run after him, shouting to him as he ran away that he could have the money and that he forgave him completely. Furthermore, he would not allow anyone to chase the thief.
The judge interrupted the lawyer saying, "My dear advocate, do you really believe that story?"
He replied "Your Honor, I don't know if the story is true or not. But they don't tell stories like that about you or me."
((K'tzeis Ha-Shemesh Bi-Gvuraso, p. 200)