It is narrated from Sayyiduna Zayd bin Thabit (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "Whoever makes a claim against his brother without evidence, then the one against whom the claim is made has the greater right to take the oath."
Hadith Referenceالمعجم الكبير للطبراني / باب الزاي / 4918