Behr et al (Reference Behr, Ruddock and Benn2005) rightly draw attention to the advantages of those with various forms of mental disturbance, in some circumstances, being held to be accountable for their actions (see also Reference Smith and DonovanSmith & Donovan, 1990; Prins, Reference Prins2002, Reference Prins2005: chapter 2). However, their comments concerning the degree to which alcohol and other drugs may totally erode criminal responsibility need slight qualification. It is of course true that, in general terms, the ingestion of alcohol and other drugs not only does not excuse culpability, but may in fact exacerbate it. There are, however, instances where specific intent has to be proved (as for example in homicide), where the ingestion of such substances may negate full responsibility (Homicide Act 1957, Section 2). In addition, the unknowing ingestion of alcohol, for example ‘spiking’ someone's non-alcoholic beverage with alcohol, may be held to exclude responsibility. The law on this whole topic is somewhat complicated, and has, from time to time, led to some equivocal decisions in the higher courts.