Confidentiality is considered one of the fundamental ethical duties of all lawyers as it provides "the foundation of trust and loyalty upon which the solicitor-client relationship is based" (Graham, Legal Ethics, 3rd ed at 191). A lawyer has a duty to hold in strict confidence all information concerning the client’s affairs and business obtained during the course of their professional relationship, and cannot disclose this information unless authorized by the client or required by law.
Privilege is a narrower concept than confidentiality. Not all information that falls within a lawyer’s duty of confidentiality is considered privileged. "To qualify as privileged solicitor-client communication, the communication between the client and lawyer must not only be made in confidence, but also relate to legal advice" (Hubbard, The Law of Privilege in Canada at 11.65).
For discussion of the ethical confidentiality rule and the evolution of the law of privilege, see Malcolm Mercer, “Boiling Frogs, Privilege and Professional Conduct” (Slaw, March 7, 2016).
This guide is intended as a starting point for research into these complex and closely related topics. Selected sources relevant to current legal practice are organized into 3 sections: confidentiality, privilege and practice resources.