diagnosed with a mental illness, whose offending is construed as relating to an 'external cause', and by implication, not one for which the individual is responsible. Personal construct theory offers a framework for understanding how offenders see the world, an understanding of why many individuals show an apparent failure to learn from past experiences, an understanding of resistance to change, a collaborative way of working with the client in which they take some responsibility for the process of change, and techniques such as the repertory grid, for understanding the structure and content of construing, and for measuring change. It is complementary to other theoretical approaches and nomothetic forms of assessment, and provides an insight into what is unique about that particular individual.
Finally, it could perhaps be argued that the advantages that PCT has to offer the forensic clinician have not been matched by progress in the research setting. It is notable that many of the key studies of the construing of mentally disordered offenders are now twenty to thirty years old, and whilst time has not diminished the significance of their results, there has been a dearth of more recent publications building on that earlier work. Dolan and Coid (1993) concluded that a lack of methodologically sound studies meant that there was no empirical evidence to support clinicians' pessimism about the treatability of personality disorders, and that further research was urgently required. Several years on, subsequent reviews have reached similar conclusions (Bateman & Fonargy, 2000; Perry et al., 1999). As discussed earlier, the UK Government is currently proposing new legislation for the detention of individuals diagnosed with severe personality disorder who pose a significant risk to others, and removing the 'treatability' criterion from the Mental Health Act. This means that as well as a need for a collaborative and empathic way of working, there is a need for PCT oriented clinicians and researchers (this author included!) to contribute to the published literature about the treatment of this challenging group of individuals.