Wikipedia:AGF

When disagreement occurs, try to the best of your ability to explain and resolve the problem, not cause more conflict, and so give others the opportunity to reply in kind. Consider whether a dispute stems from different perspectives, and look for ways to reach consensus.

When doubt is cast on good faith, continue to assume good faith yourself when possible. Be civil and follow dispute resolution procedures, rather than attacking editors or edit-warring with them. If you wish to express doubts about the conduct of fellow , please substantiate those doubts with specific diffs and other relevant evidence, so that people can understand the basis for your concerns. Although bad conduct may seem to be due to bad faith, it is usually best to address the conduct without mentioning motives, which might exacerbate resentments all around.

Be careful about citing this principle too aggressively. Just as one can incorrectly judge that another is acting in bad faith, so too can one mistakenly conclude that bad faith is being assumed; exhortations to "Assume Good Faith" can themselves reflect negative assumptions about others.

Violation of policies—such as engaging in sock-puppetry, violating consensus, and so on—may be perpetrated in either good or bad faith. There are processes for dealing with all of these, and sanctions for repeated violation of policy will apply regardless of whether bad faith was involved or not.

When dealing with possible copyright violations, good faith means assuming that editors intend to comply with site policy and the law. That is different from assuming they have actually complied with either. Editors have a proactive obligation to document image uploads, etc. and material may be deleted if the documentation is incorrect or inadequate. Good faith corrective action includes informing editors of problems and helping them improve their practices.

Even if bad faith is evident, do not act uncivilly yourself in return, attack others, or lose your cool over it. It is ultimately much easier for others to resolve a dispute and see who is breaching policies, if one side is clearly acting appropriately throughout.

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Wikipedia