A guilty plea may be withdrawn before judgment for good cause shown by clear and convincing evidence. (Pen. Code, 1018 ; People v. Cruz (1974) 12 Cal.3d 562, 566.) A defendant may show good cause under Penal Code section 1018 by demonstrating he or she received ineffective assistance of counsel. (In re Alvernaz (1992) 2 Cal.4th 924, 934.) Penal Code section 1018 provides in part: "On application of the defendant at any time before judgment or within six months after an order granting probation is made if entry of judgment is suspended, the court may, and in case of a defendant who appeared without counsel at the time of the plea the court shall, for a good cause shown, permit the plea of guilty to be withdrawn and a plea of not guilty substituted." "'"In order to establish a claim of ineffective assistance of counsel, defendant bears the burden of demonstrating, first, that counsel's performance was deficient because it 'fell below an objective standard of reasonableness . . . under prevailing professional norms.' Unless a defendant establishes the contrary, we shall presume that 'counsel's performance fell within the wide range of professional competence and that counsel's actions and inactions can be explained as a matter of sound trial strategy.' . . . If a defendant meets the burden of establishing that counsel's performance was deficient, second he or she also must show that counsel's deficiencies resulted in prejudice, that is, a 'reasonable probability that, but for counsel's unprofessional errors, the result of the proceeding would have been different.' "' " (People v. Salcido (2008) 44 Cal.4th 93, 170.) Thus, "A meritorious claim of constitutionally ineffective assistance must establish both: '(1) that counsel's representation fell below an objective standard of reasonableness; and (2) that there is a reasonable probability that, but for counsel's unprofessional errors, a determination more favorable to defendant would have resulted. If the defendant makes an insufficient showing on either one of these components, the ineffective assistance claim fails.'" (People v. Holt (1997) 15 Cal.4th 619, 703, quoting People v. Rodrigues (1994) 8 Cal.4th 1060, 1126 because ineffective assistance of counsel fails on an insufficient showing of either element, a court need not decide the issue of counsel's alleged deficiencies before deciding if prejudice occurred; see also Strickland v. Washington (1984) 466 U.S. 668, 687 104 S.Ct. 2052.) "'"Reviewing courts defer to counsel's reasonable tactical decisions in examining a claim of ineffective assistance of counsel , and there is a 'strong presumption that counsel's conduct falls within the wide range of reasonable professional assistance.'"' " (People v. Jones (2003) 29 Cal.4th 1229, 1254.) "'In determining whether counsel's performance was deficient, a court must in general exercise deferential scrutiny .'" (People v. Brodit (1998) 61 Cal.App.4th 1312, 1335, quoting People v. Ledesma (1987) 43 Cal.3d 171, 216.) "'Although deference is not abdication . . . , courts should not second-guess reasonable, if difficult, tactical decisions in the harsh light of hindsight.'" (People v. Brodit, supra, at p. 1335, quoting People v. Scott (1997) 15 Cal.4th 1188, 1212.)