Wikipedia:Put up or shut up

Occasionally in a heated dispute, someone may post on the administrators' noticeboards regarding the conduct of another editor but without providing any evidence (in the form of diffs) to back it up. This is not helpful: negative commentary directed at other editors is hurtful and creates drama at the best of times, and it is sadly all too easy to mischaracterise or outright lie about what another editor did. As such, one should always provide evidence when requested (or ideally to begin with) if one is making such allegations. Otherwise, editors should not expect their allegations to be taken seriously, and indeed may be considered to be acting vindictively.