What must a lawyer obtain to reveal a client's confidential information?

To reveal a client's confidential information, a lawyer must obtain informed consent or authorization from the client. This principle is rooted in the attorney-client privilege, which emphasizes the importance of maintaining the confidentiality of the communication between a lawyer and their client. Informed consent means that the client understands the nature of the disclosure, the potential consequences, and still agrees to it, ensuring that they are making a knowledgeable decision.

This requirement for consent reinforces the trust between the lawyer and the client, allowing for candid communication essential for effective legal representation. It protects clients' privacy and encourages full disclosure, which can lead to better legal advice and advocacy.

The other options do not meet the ethical standards required. Parental or guardian consent may apply in cases involving minors but is not the standard for adult clients. Verbal agreements, lacking the formality and clarity of informed consent, may not meet the necessary legal and ethical criteria. Additionally, the notion that no consent is needed under any circumstance contradicts the foundational principles of client confidentiality in the legal profession.