Must the Imam accept the notification of the followers if two reliable individuals confirm the error?
Chapter on the Two Prostrations of Forgetfulness
Al-Mughni
Book of Prayer
Primary text
If two trustworthy individuals inform the Imam of his error, he is obligated to accept their statement and return to the correct action, regardless of whether he suspects they are correct or mistaken. The evidence for this obligation is the action of the Prophet (peace be upon him) in the incident of Dhu al-Yadayn, where he returned to the account of Abu Bakr and 'Umar after asking them, 'Is what Dhu al-Yadayn says true?' This indicates he accepted their confirmation despite his initial doubt. Furthermore, the command to use tasbih is intended to remind the Imam, thus requiring adherence to their reported correction, as per the Hadith where the Prophet (peace be upon him) said regarding forgetting: 'If I forget, then remind me,' meaning by tasbih.
Supporting text
Al-Shafi'i holds that if the Imam suspects the two individuals are mistaken, he should not act upon their statement. This is analogous to a judge who forgets a ruling but is then informed by two witnesses; if he doubts their statement, he does not act upon it. Abu al-Khattab suggests that the Imam must return to their statement even if he is certain of his own correctness, like a judge accepting testimony that contradicts his personal knowledge, but this is incorrect as one should not follow others into known error. If the Imam is certain of his correctness and the followers are mistaken, he must not follow them.