How to Deny Manifest Innovations

Q: When we deny the errors and innovations committed by those who have influence over people, and whose innovations spread, especially in matters of creed where they exaggerate, and when we deny an innovation, some people object on the grounds that the truth requires mentioning the person's good deeds and faults, and that their struggle in da'wah and their seniority prevent their public criticism. We ask for clarification of the correct methodology: Is it obligatory to mention the good deeds? And does a prior record in da'wah exempt one from mentioning their well-known errors that are circulating among people?
A reader from Egypt.

A: It is obligatory for the people of knowledge to deny manifest innovations and sins with the evidence of the Shari'ah, through encouragement and warning, and in a good manner. It is not obligatory to mention the good deeds of the innovator in doing so. However, if the one who enjoins good and forbids evil mentions them to the person who committed the innovation or the evil, as a reminder of their good deeds and to encourage them to repent, that is good and is among the causes for the acceptance of the call and the return to repentance. May Allah guide them all.