Personality disorder as a diagnosis: stereotyping and discrimination aren’t avoidable complications, they are inherent to the diagnostic process.
In clinical practice, a full diagnosis typically consists in the description of a particular presentation coupled with an account of the associated (causal) pathology that explains the presentation. Thus: you are breathless and I can’t hear breath sounds on the right side when I listen with my stethoscope (the presentation) because you have fluid surrounding your lung due to tuberculosis (the explanatory pathology). Diagnosis in psychiatry is rarely full in this way, typically consisting only of a description of the presentation.
If we consider the diagnosis of personality disorder in this light, does it make sense? The diagnostic statement is that the person is the presentation, and although there is assumed to be some sort of underlying deficit in psychological function that constitutes the associated (causal) pathology, it has to be said that after 100 years of inquiry what it is remains to be revealed. We are left with the diagnostic statement – your emotions, actions, thoughts aren’t symptoms of some condition you have; they are simply the expression (presentation) of your personality and therefore who you are is a mental disorder.
If that’s right, can debate about the status of the diagnosis be bracketed with debates about the clinical or social status of autism or physical disability? That is, the diagnosis can be criticised for pathologizing diversity or for essentialising the individual who becomes the problems they present? I don’t think this quite works as an analogy. For example, there is no ineluctable presentation in personality disorder which is why categorising sub-types has proved such a failure. Autism is autism is autism, while psychopathy can look like any number of things.
Apart from the mutability difference, there is something different from the neuro-diversity analogy in the way the “disorder” of personality disorder is defined – not just in social or interpersonal terms but in judgemental terms. The judgements are, at root, about acceptability of behaviour, emotional expression and so on.
So, making a diagnosis of personality disorder isn’t stereotyping or stigmatising as an unfortunate side-effect of the way some ill-informed people choose to treat those so diagnosed, it is inherent to the diagnostic process. If we say that who somebody is constitutes a mental disorder the features of which are socially and personally undesirable, and this “who somebody is” fits them in a category of similar people with the same mental disorder, then how could it be other than stereotyping and stigmatising, with the resulting responses being those we might expect towards anybody who is by definition undesirable?