Final answer:
In Strickland v. Washington, the rule established by the Supreme Court is that to prove ineffective assistance of counsel, a defendant must show that counsel's performance was deficient and that it affected the outcome of the case.
Step-by-step explanation:
In the case of Strickland v. Washington, the Supreme Court established a rule relating to ineffective assistance of counsel. To obtain relief, a defendant must prove two components:
- Counsel's performance fell below an objective standard of reasonableness.
- The deficient performance of counsel gives rise to a reasonable probability that, if counsel had performed adequately, the result of the proceeding would have been different.