You are reminded that a solicitor must (a) have instructions from his or her client and (b) be satisfied when taking instructions, that his or her client has the capacity to give instructions to relation to that matter.
Solicitors should always be alert to any indications of possible vulnerability, whether related to concerns about capacity or other matters, such as the potential exercise of undue influence by another party.
If there is any doubt as to a client's capacity to instruct in a particular case, expert guidance may be sought from an appropriate medical professional, but the solicitor retains responsibility for compliance with the rule and cannot abdicate that responsibility to a medical professional.
Solicitors cannot simply rely upon the legal presumption of capacity, but must take reasonable steps to facilitate the exercise of capacity, including in the matter of instructing a solicitor.
Reference should be made to the Guidance on Vulnerable Clients