Model Rules of Professional Conduct
Transactions With Persons Other Than Clients
Rule 4.4 Respect For Rights Of Third Persons
(a) In representing a client, a lawyer shall not use means that have no substantial purpose other than to embarrass, delay, or burden a third person, or use methods of obtaining evidence that violate the legal rights of such a person.
(b) A lawyer who receives a document relating to the representation of the lawyer's client and knows or reasonably should know that the document was inadvertently sent shall promptly notify the sender.
