I think that the answer to the first question (which deals with the question whether the accountants MUST provide copies) is no, unless of course the documents belong to the client. Whether that is the case depends on what documents are being requested.
In any event, I do not think that section 20(3) should be in point at all if the documents in fact belong to the client. If they belong to the client, it follows that they are in the power or possession of the client (all he needs to do is take appropriate action to obtain them) and if I were the previous accountant, I would certainly argue that a notice under section 20(1) should be given to the former client and a third party notice under section 20(3) is not appropriate. I have put this point to General Commissioners to whom an application for consent to a section 20(3) notice had been made and they refused to give consent to the notice, agreeing with me that a section 20(1) notice had to be given.
It is possible that, while the documents in question belong to the client, the accountant may have a lien over them for unpaid fees. Again, if I were the previous accountant, I would argue in those circumstances (as I have done successfully in the past ) that it was wrong to proceed under section 20(3) because the documents were in the power of the client - all he had to do to obtain them was to take out his cheque book!
As regards the question of courtesy raised in the second paragraph, in an ideal world, "maths" would be quite right. However, courtesy frequently evaporates when money is at stake and regrettably, not all accountants are professionally qualified and some of those who are do not always adhere to their professional body's guidelines.
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