Mental Health

At Sonn Macmillan Walker we have the experience, understanding and compassion to represent individuals who are particularly vulnerable due to psychiatric or psycholgical issues.   

The course of a criminal case for individuals with mental health concerns can be significantly different, in respect of entering pleas, the trial procedure and sentencing.   

We have strong working connections with leading psychiatrists, psychologists, and intermediaries across the country and our solicitors are alert and adept at recognising when our clients may benefit from an assessment by an expert.  

Fitness to Plead  

Where mental health affects a defendant’s ability to understand the charge they face, or participate in the proceedings, there may be a concern about their ‘fitness to plead’.  If we have any such concerns that our clients may not have the requisite capacity we will ensure assessments are undertaken as the Court will require the opinion of two suitably qualified experts before a defendant is found to be unfit.  If an individual is found to be unfit it does not mean the proceedings will conclude but they will follow a different course, considering only whether the defendant committed the alleged act.     


If a defendant is particularly unwell at the time of the the alleged offence, they may have a defence of ‘insanity’.  This is again something that will require the instruction of experts and in appropriate cases our team will consider whether we require assessments to be undertaken.  This defence will only apply in a case where a defendant has a "defect of reason" arising from a "disease of the mind" that at the time of committing the act, they did not know the nature and quality of their actions; or if they did know the nature and quality, that they did not know that what they were doing was wrong.  

This is a complex area but at Sonn Macmillan Walker, we are alive to the potential this defence can offer individuals and the leading experts to consult in respect of reports.   


We are always keen to ensure our clients receive the support they require during Court proceedings.  Some of our clients may need assistance in communicating as a result of mental health or learning difficulties. They might need help to understand and process complex information. An intermediary is a communication professional, and they can work alongside a legal team, supporting clients to ensure that all their needs are met. With approval from the court, intermediaries can be granted to assist either when defendants give evidence, or during a whole trial. We are experienced in knowing when to ensure an intermediary assessment is undertaken, and how to effectively use an intermediary to support our clients.  

These are just some of the examples of how we assist vulnerable clients, we can also instruct psychiatrists to comment on whether they had the capacity at the time of an alleged offence to form the relevant intent, or if they have certain vulnerabilities meaning they should be assessed in respect of being a victim of modern slavery. Our team are consistent in identifying vulnerable defendants and ensuring they are represented accordingly.  

Notable Cases

Our recent cases in this area.

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