Sayyiduna Anas (may Allah be pleased with him) said that the Prophet (peace and blessings be upon him) said three times: "The Imams (leaders) are from Quraysh. Just as I have a right over you, so do they, as long as they keep doing three things: showing mercy, being equitable, and being just in their judgements." [Hasan]
Hadith Referenceالسنن الكبرى للبيهقي / كتاب قتال أهل البغي / 16544