The question of motive is a rather difficult one to address as homicides can be and generally are classified in a variety of different ways. As Wilson and Daly have pointed out, ‘the prevailing criminological conception of motives in homicide is a wooly amalgam of several potentially independent dimensions: spontaneity versus premeditation, the victim–offender relationship, and only a relatively small dose of […] substantive issues.’ The solution offered by Wilson and Daly is to try and isolate the substantive issue and to make it the primary focus of inquiry. While this is a perfectly valid approach, there are risks involved in privileging one factor over another when attempting to understand the motives behind violent activity. In some cases, the substantive issue can be the most significant factor. This is evident, for instance, in homicides involving robbery where it is generally the desire to take the victim's property that is central to the act rather than necessarily the relationship between the parties. In other cases, it is the relationship between the parties that is to the fore. For instance, in cases of spousal homicide, the act may arise from a relatively minor argument, but its real motivation may lie somewhat deeper in the relationship between husband and wife.

Thus, in some cases, it is clearly the relationship between the parties that is the primary cause of the dispute and it is the tension within this relationship that elevates the substantive issue to a position of significance. In other cases, it is the substantive issue which upsets or disrupts the relationship between the parties. To exclude either of these factors would be a mistake, but in order to classify the cases it is necessary to emphasise or privilege what we believe to be the dominant element in the act. This is, of course, by no means a foolproof method of classification and is obviously quite a subjective exercise. It is, however, a necessary one if any wider understanding of the contexts in which these homicides occurred is to be reached. The discussion here will focus on the four main categories of cases which are dealt with in this book, namely, personal disputes, personal family disputes, land-related disputes and, finally, disputes arising from sectarian animosity.