The key points of Henning's article are:
1. Henning opens:
There may be no more fertile ground for obtaining damaging information in an investigation than from a lawyer about a client. People tend to be more open with their lawyers, or perhaps worse, try to lie to them to use legal advice to keep from getting caught.JAT Note: There is a third possibility. Some clients may be using the lawyer in a way that can implicate the lawyer in the skulduggery, so as make the lawyer a bargaining chip with prosecutors if the client needs it later. In this regard, a standard first meeting line I have with clients in criminal matters is that, if anyone in this room is going to jail, it will not be me. Client representation in criminal cases requires warm zeal for the client, but warm zeal does not require that the lawyer improperly extend himself for the client.
2. Henning discusses what prosecutors can do to get to the lawyer's information. In Zukerman, of course, they got to the lawyer's information by successfully asserting the crime-fraud exception to the attorney-client privilege. That put the lawyers in the uncomfortable position of testifying against the client. And, it put the lawyers in an uncomfortable position with respect to their continuing representation of a valuable client.
3. Henning suggests that the presence of lawyers in offshore planning raises the possibility that otherwise confidential communications might be pierced. He mentions specifically the Panama Papers disclosures.
4. Henning questions the use of this prosecutor tool as leverage by prosecutors to chill the attorney-client relationship, discussing certain ethical rules applicable to prosecutors.