Intentionality
Many definitions of impoliteness flag up the importance of intentionality, that is, whether the producer of impoliteness meant to be impolite. Understanding actions as intentional or otherwise is a fundamental part of human thinking and behaviour (and also possibly that of some animals, cf. Call et al. 2004). It is key to legal systems. In British law, for example, it plays a role in judgements of murder versus manslaughter. Moreover, it is key to social norms: we may wish and plan our actions to be in accordance with social norms, and to be recognised as intending to act so.
The key point of interest for impoliteness is whether an understanding of a behaviour as intentionally impolite differs from an understanding of the same behaviour as unintentionally (e.g. accidentally) impolite. Studies in social psychology have repeatedly shown that aggressive behaviours perceived to be intentional are considered more severe and are likely to receive a strong response, and studies in the area of social communication have found that hurtful verbal behaviours and messages are considered more hurtful, malicious, immoral, etc., if they are considered intentional. The evidence is compelling that impolite behaviour perceived to be intentional is likely to be considered more impolite than those that are not. And this seems to fit intuitively: one can hardly blame someone for accidents.
However, I am not convinced that (full) intentionality is an essential condition for impoliteness. My data shows that people can, at least in some contexts, still take serious offence in the absence of full intentionality being understood. Consider this example:
Went to meet a friend who I hadn't seen for a long time, the first thing he said was: "you've got more 'curves' than you used to have! Have you put some weight on? You've got a right J-Lo bum now" - implying I was now fat!
I replied by saying "thanks" sarcastically
This informant comments: "I felt embarrassed and fat! Because no-one has ever said it to me before, I took it as a huge insult and he wasn't joking when he said it to me. He wasn't malicious". Moreover, on the rating scales I supplied, she rated it very highly for offence but lowly for how intentional she thought it was.
One way of accommodating such examples is to consider intentionality to have a number of components (e.g. desire for certain effects, a plan of action, ability to carry out the plan, responsibility for the action, foresight of consequences). Weaker intentionality would involve such components as responsibility for or control over an act, or, at an even further remove, the foreseeability of an act. In the example above, whilst the offensive consequences of the utterance might not have been considered intentional in all respects, the informant may well have considered them foreseeable, and thus consequences that should have been prevented by a friend. One might predict that judgements of impoliteness based on foreseeability are more likely in contexts (1) involving salient relationships, where transgressions have clearer consequences, and/or (2) close relationships, where the participants know each other well and thus are in a position to make stronger assumptions about foreseeability.