Ineffective assistance of counsel refers to a situation in which a criminal defendant's legal representation fails to meet the minimum standards of competence and diligence expected from attorneys. It is a constitutional claim that arises under the Sixth Amendment of the United States Constitution, which guarantees the right to effective assistance of counsel to defendants in criminal proceedings. Therefore, ineffective assistance of counsel is a common habeas corpus claim, in which convicted individuals petition that their imprisonment or detention is unlawful.
The 1984 landmark case of Strickland v. Washington established a 2-part test to determine whether a criminal defendant’s attorney has failed to meet the minimum expectations for effective counsel in criminal proceedings guaranteed by the Sixth Amendment.
To prove ineffective assistance of counsel, a defendant must show:
- That their trial lawyer's conduct fell below an "objective standard of reasonableness" and,
- "a reasonable probability that, but for counsel's unprofessional errors,” the outcome of the criminal proceeding would have been different.
Both elements must be proved in order for a claim of ineffective counsel to succeed.
The Strickland court also noted that judicial evaluation of the attorney’s performance “must be highly deferential.” For example, a convicted defendant who alleges ineffective assistance must identify the specific “acts or omissions of counsel” they believe falls below the objective standard of reasonableness. Additionally, the burden lies with the defendant to prove that they were “harmed by [their] attorney’s conduct” and that there is a “reasonable probability” that the outcome of the criminal proceeding would have been different if not for the attorney’s errors.
[Last updated in June of 2023 by the Wex Definitions Team]