I.... can't tell who is joking and who is serious anymore ITT. The whole thing has become so surreal.
Cat- just in case you weren't joking, a subpoena would be issued to the bank, but it would have to target specific accounts.
I am sure you and FSD understand and are just being inartful with your explanations, but for the sake of the JV lawyers out there I should clarify that a subpoena to a bank (especially from the federal government) does not have to list specific accounts and can simply ask for any accounts pertaining to a certain person or entity so long as the description is clear enough for the bank to determine they have the correct person/entity (usually by DOB, SSN, or EIN).
Of course, asking for any accounts of someone "close to" Trump would be too vague, but I would not expect an anonymous source with knowledge of the subpoena to provide that list as the person may not have been that close to the actual drafting and/or would not want to give away their identity in the likely event that only a handful of people were actually involved.
As to whether a bank has constitutional rights like free speech, I have no idea. They're not corporations.