Should I send a client care letter to the principal or the court appointed deputy

I am instructed by a court-appointed deputy for an elderly woman who has lost capacity. Is my client the deputy or the patient? To whom should I send a client care letter?

A solicitor must act on the instructions of the client and – including when these are given on the client’s behalf by another person owing to the client’s lack of capacity – always in the client’s best interests.

This overriding duty to the client is owed to the woman who is the principal, even if you’re taking instructions from an agent such as a deputy or attorney.

See Re EG [1914] 1 Ch 927 and section 19(6) of the Mental Capacity Act 2005.

Where you believe that the instructions given are not in the best interests of the principal, you should decline to act.

You should not terminate the retainer at that stage but consider whether you can act for either the agent or the principal on the basis that each needs to be separately represented.

The client care letter should be addressed to the principal where she has capacity.

Otherwise, it should be addressed and sent to the agent, although it should identify the principal as the client and explain the solicitor-client relationship, as in this situation.

There are specific situations in which a solicitor will act directly for the agent, for instance where:

  • the attorney instructs the solicitor to apply to the Court of Protection for registration of a lasting power of attorney
  • a prospective deputy instructs the solicitor to apply to the Court of Protection for the appointment of the deputy

For more information, see our Elderly Client Handbook (6th edition) or contact the Practice Advice Service.


While every effort has been made to ensure the accuracy of the information in this article, it does not constitute legal advice and cannot be relied upon as such. The Law Society does not accept any responsibility for liabilities arising as a result of reliance upon the information given.

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