Final answer:
Attorneys in a firm must avoid representing a client when conflicts of interest arise, as this can undermine their ability to provide effective legal representation and violate the Sixth Amendment's Assistance of Counsel Clause.
Step-by-step explanation:
When attorneys are associated in a firm, none of them may knowingly represent a client when there is a conflict of interest that can affect the attorney's ability to provide competent and dedicated representation to each client.
According to landmark rulings such as Glasser v. United States, a lawyer's conflict of interest from simultaneous representation of codefendants can violate the Sixth Amendment's Assistance of Counsel Clause.
Likewise, Strickland v. Washington requires that for a defendant to obtain relief due to ineffective counsel, they must prove that the counsel's performance was deficient and had an adverse effect on the outcome. Counsel also has an imperative duty to inform clients about potential immigration consequences after a conviction, as established in Padilla v. Kentucky.
The U.S. Supreme Court has made it clear through various rulings, such as in Betts v. Brady (later overruled by Gideon v. Wainwright), that the representation by legal counsel is a fundamental right for those accused of serious crimes. This right was eventually extended to anyone facing jail time, ensuring the accused has adequate legal representation, which may even be a public defender paid by the state if the accused cannot afford one.