Final answer:
A lawyer must not assist a client in perjury and is obligated to take remedial measures if perjury occurs, such as advising the client against it or seeking to withdraw from the case. The lawyer must balance the sixth amendment rights of the client with the need to maintain the integrity of the legal system, all while adhering to professional conduct rules.
Step-by-step explanation:
If a lawyer is aware that her criminal defendant client plans to commit perjury or has already done so, the lawyer faces a serious ethical dilemma. According to the American Bar Association Model Rules of Professional Conduct and various legal precedents, a lawyer has a duty to uphold the legal system and cannot assist a client in conduct that the lawyer knows is criminal or fraudulent. This includes knowingly allowing a client to commit perjury.
The lawyer must take reasonable remedial measures to rectify the situation, which may include confidentially advising the client against committing perjury, seeking to withdraw from the case, and in extreme situations, notifying the court of the perjury if it has already occurred and cannot otherwise be remediated. However, the lawyer is also bound by attorney-client privilege and must not disclose the client's intentions or past actions to others. Choices made by the lawyer must adhere to professional rules of conduct and may vary depending on the jurisdiction.
In the context of Strickland v. Washington and Glasser v. United States, it is imperative that the defense attorney avoid any action that may be construed as ineffective assistance of counsel or as creating a conflict of interest. The primary goal is to balance the sixth amendment rights of the client with the integrity of the legal proceedings.