I deal a lot with protection of information, data protection and personal information at my work place and I also inspect systems for this.

I think there should be a protocol known by all forum members governing the publication of PM's. This should detail the types of situations in which a PM could be published (I would suggest such situations should be rare), who by, whether any other agreement would need to be sought (for example, one moderator might need to seek the agreement of another moderator to go ahead), whether or not authors are to be named, and what steps should be followed prior to doing so, for example, consulting with or notifying the author. I believe this to be a professional and courteous system and one in which all members and moderators would know exactly where they stand. If the correct protocol is followed each time, there should be no need for criticism of the moderator or surprise on behalf of the author of the PM. In addition, if a robust system is imposed in such cases it should always ensure that the correct considerations are made before taking such a step, and that a judgement has been made about the reasons for it, and how the forum benefits from it.