Can a defendant withdraw his guilty plea before judgment?

"A defendant who seeks to withdraw his guilty plea may do so before judgment has been entered upon a showing of good cause. [Citations.] `[Penal Code] Section 1018 provides that . . . "On application of the defendant at any time before judgment . . . the court may, . . . for good cause shown, permit the plea of guilty to be withdrawn and a plea of not guilty substituted." Good cause must be shown for such a withdrawal, based on clear and convincing evidence. [Citation.]' [Citations.] `To establish good cause, it must be shown that defendant was operating under mistake, ignorance, or any other factor overcoming the exercise of free judgment. [Citations.] Other factors overcoming defendant's free judgment include inadvertence, fraud or duress. [Citations.]' [Citation.] `The burden is on the defendant to present clear and convincing evidence the ends of justice would be subserved by permitting a change of plea to not guilty.' [Citation.]" (People v. Weaver (2004) 118 Cal.App.4th 131, 145-146.)