It is narrated from Sayyiduna Abu Hurayrah (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "The imams lead you in prayer. If they lead the prayer correctly, there is reward for you and for them; but if they err, you will receive the reward, and the burden is upon them."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 4062