Who has the right to declare people open sinners or disbelievers?

Question:
May Allah reward you, Honorable Shaykh. This questioner says: Who has the right, O Honorable Shaykh, to declare people open sinners or disbelievers?

Answer:
This is the domain of the scholars of knowledge and those with insight, who know who falls under the category of disbelief, who falls under the category of open sinfulness, and who falls under the category of religious innovation. This is the exclusive jurisdiction of the scholars of knowledge.