What is the test for ineffective assistance of counsel?

To prevail on his claim of ineffective assistance of counsel, G.C. must show both that his trial attorney's performance was deficient and that the deficiency was prejudicial to his defense. (Strickland v. Washington (1984) 466 U.S. 668, 686.) We find it unnecessary to determine whether counsel should have raised the arguments now posited because we are satisfied that his failure to do so had no effect on the outcome. This is because the trial court was almost certain to find, on the facts before it, that Officer Zuniga had probable cause to search G.C. for cocaine. This conclusion makes it immaterial whether minor consented to the search, and also obviates any concern about the subsequent discovery of the gun, which was an inevitable consequence of G.C.'s lawful arrest for possession of cocaine.