Final answer:
A lawyer must not disclose information related to a client's representation, with some exceptions such as informed consent, court orders, or when legally required. This maintains confidential communication between lawyers and clients, fostering effective legal advice.
Step-by-step explanation:
A lawyer must always maintain the confidentiality of information relating to the representation of a client. This duty of nondisclosure is fundamental to the attorney-client relationship and is mandated by legal ethics and professional responsibility codes. However, there are exceptions to this rule, such as when the client provides informed consent for the disclosure, when the disclosure is impliedly authorized in order to carry out the representation, or when it is permitted by law or court order.
It is essential to understand that maintaining confidentiality helps to facilitate open communication between attorneys and their clients, enabling clients to receive informed legal advice. For instance, in criminal cases, a client has the right to remain silent and the right to legal counsel as outlined in the Miranda Rights and the Sixth Amendment. Non-disclosure is critical unless it infringes on specific safeguards, like preventing future crimes or fraud. Interestingly, in the landmark case of Glasser v. United States, it was held that a defense lawyer's conflict of interest arising from simultaneous representation of co-defendants violates the Assistance of Counsel Clause of the Sixth Amendment.
Furthermore, in the case of Strickland v. Washington, for a criminal defendant to obtain relief due to ineffective assistance of counsel, they must demonstrate that the counsel's performance was deficient and that this deficiency affected the case outcome.