What if you were to encode a message to your lawyer via your payments. Would that make it privileged? To me, a private transaction between parties subject to confidential privilege should also be subject to privilege.
The presence of a non-lawyer, non-client in a conversation makes it non-privileged. That is, if someone who is not privileged is part of the talk then it can't have privilege. Is your bank also your lawyer or a client of your lawyer? If not, then the presence of the third party in the transaction kills your privilege claim.
And having your bank share your lawyer with you might potentially open up conflict of interest questions, since your legal rights and your banks might diverge.
In-house council for a company get away with this (for internal communications) because they are lawyers for the company (right up until your interests diverge from that of the company, at which point you really want your own lawyer), but for your bank this stops being true.
Basically, you are thinking about law like an engineer, not a lawyer.
Someone else asked this upstream, but don’t you “share” your privileged communications with your (and your lawyer’s) email provider when corresponding without E2E encryption?
A third party can be necessary to facilitate the communication between the client and the attorney. A clearer example was if you needed an interpreter to speak to your lawyer - surely that conversation remains privileged and the third party in the room cannot disclose what was learned?
In your world, wouldn't every tax cheat just conceal money by routing it through their law firm? Then the government can never find out how much money you have because it would be illegal to subpoena the firm, right?
