Threats or actions which expose other Wikipedia editors to political, religious or other persecution by government, their employer or any others. Violations of this sort may result in a block for an extended period of time, which may be applied immediately by any administrator upon discovery. Admins applying such sanctions should confidentially notify the members of the Arbitration Committee of what they have done and why.
These examples are not inclusive. Insulting or disparaging an editor is a personal attack regardless of the manner in which it is done. When in doubt, comment on the article's content without referring to its contributor at all.
The prohibition against personal attacks applies equally to all Wikipedians. It is as unacceptable to attack a user with a history of foolish or boorish behavior, or even one who has been subject to disciplinary action by the Arbitration Committee, as it is to attack any other user. Wikipedia encourages a positive online community: people make mistakes, but they are encouraged to learn from them and change their ways. Personal attacks are contrary to this spirit and damaging to the work of building an encyclopedia.
If you feel that a response is necessary and desirable, you should leave a polite message on the other user's talk page. Do not respond on a talk page of an article; this tends to escalate matters. Likewise, it is important to avoid becoming hostile and confrontational yourself, even in the face of abuse. Although templates have been used at times for this purpose, a customized message relating to the specific situation is often better received. When possible, try to find compromise or common ground regarding the underlying issues of content, rather than argue about behavior.
Personal attacks do not include civil language used to describe an editor's actions, and when made without involving their personal character, should not be construed as personal attacks, for instance, stating "Your statement is a personal attack..." is not itself a personal attack.
Attacks that are particularly offensive or disruptive (such as physical or legal threats) should not be ignored. Extraordinary situations that require immediate intervention are rare, but may be reported on the administrators' noticeboard.
Recurring, non-disruptive personal attacks that do not stop after reasoned requests to cease should be resolved through the dispute resolution process. Especially when personal attacks arise as the result of heated debate over article content, informal mediation and third-party opinions are often the best ways to resolve the conflict. Similarly, Wikiquette alerts offers a "streamlined" source of outside opinion. In most circumstances, problems with personal attacks can be resolved if editors work together and focus on content, and immediate administrator action is not required.
The community has not reached a consensus about whether on-wiki personal attacks should be removed, although it has been a topic of substantial debate, and an essay about removing attacks has been written on it. To cite the Arbitration Committee:
The remove personal attacks guideline (and the application thereof) is controversial. It has often been abused by malefactors, and may not have community consensus. It should, at most, be interpreted strictly and used sparingly.
Removing unquestionable personal attacks from your own user talk page is much less of a concern than removing comments from other pages in Wikipedia. For text elsewhere, where such text is directed against you, removal should be limited, except in unusual circumstances, to comments that are listed above as clear violations of this policy.
Wikipedia cannot regulate behavior in media not under the control of the Wikimedia Foundation, but personal attacks elsewhere create doubt as to whether an editor's on-wiki actions are conducted in good faith. Posting personal attacks or defamation off-Wikipedia is harmful to the community and to an editor's relationship with it. Such attacks may be regarded as aggravating factors by administrators and may be used as evidence in the dispute-resolution process, including in Arbitration cases.
Links or references to off-site personal attacks against Wikipedians should be removed. The removal of such material is not subject to the three-revert rule. Linking to material that attacks, harasses, or violates the privacy of any Wikipedian is not permitted and doing so repeatedly may result in a block.
Editors who persist in posting links to personal attacks against Wikipedians on any other site, will be treated in the same way as editors who persist in posting personal attacks on Wikipedia.
Although editors are encouraged to ignore or respond politely to isolated personal attacks, that should not imply that they are acceptable or without consequences. A pattern of hostility reduces the likelihood of the community assuming good faith, and can be considered disruptive editing. Users who insist on a confrontational style marked by personal attacks are likely to be handled through the dispute resolution process, possibly including the serious consequences of arbitration, and may become subject to a community ban.
In extreme cases, even isolated personal attacks may lead to a block for disruption. Legal threats, death threats, and issues of similar severity, in particular, may result in a block without warning. However, administrators are cautioned that other resolutions are preferable to blocking for less severe situations when it is unclear if the "conduct severely disrupts the project". Recurring attacks are proportionally more likely to be considered "disruption". Blocking for personal attacks should only be done for prevention, not punishment. A block may be warranted if it seems likely that the user will continue using personal attacks.
↑The ArbCom has ruled that "[a] website that engages in the practice of publishing private information concerning the identities of Wikipedia participants will be regarded as an attack site whose pages should not be linked to from Wikipedia pages under any circumstances,"  and that "[l]inks to attack sites may be removed by any user; such removals are exempt from 3RR. Deliberately linking to an attack site may be grounds for blocking." 
↑ In a subsequent arbitration, the committee rejected this principle as "too broad."