Psychiatric inpatients with capacity may be treated paternalistically under the Mental Health Act 1983. This violates bodily autonomy and causes potentially significant harm to health and moral status, both of which may be long-lasting. I suggest that such harms may extend to killing moral persons through the impact of psychotropic drugs on psychological connectedness. Unsurprisingly, existing legislation is overwhelmingly disliked by psychiatric inpatients, the majority of whom have capacity. I present four arguments for involuntary treatment: individual safety, public safety, authentic wishes and protection of autonomy. I explore these through a case study: a patient with schizophrenia admitted to a psychiatric hospital under the Mental Health Act 1983 after an episode of self-poisoning. Through its discussion of preventative detention, the public safety argument articulates the (un)ethical underpinnings of the current position in English law. Ultimately, none of the four arguments are cogent—all fail to justify the current legal discrimination faced by psychiatric inpatients. I conclude against any use of involuntary treatment in psychiatric inpatients with capacity, endorsing the fusion approach where only psychiatric patients lacking capacity may be treated involuntarily.