In Kercheval v. United States (1927) 274 U.S. 220, the petitioner had initially pled guilty but had been allowed to withdraw his plea and plead not guilty when he received a harsher sentence than anticipated. (Id. at p. 221.) The trial court then allowed the prosecution to introduce evidence of petitioner's guilty plea as part of its case in chief. (Id. at pp. 221-222.) The U.S. Supreme Court concluded a withdrawn plea of guilty is inadmissible at trial on the substituted plea of not guilty. (Id. at p. 223.) It explained: "A plea of guilty differs in purpose and effect from a mere admission or an extra-judicial confession; it is itself a conviction. Like a verdict of a jury it is conclusive. More is not required; the court has nothing to do but give judgment and sentence. Out of just consideration for persons accused of crime, courts are careful that a plea of guilty shall not be accepted unless made voluntarily after proper advice and with full understanding of the consequences. When one so pleads he may be held bound. But, on timely application, the court will vacate a plea of guilty shown to have been unfairly obtained or given through ignorance, fear or inadvertence. Such an application does not involve any question of guilt or innocence. The court in exercise of its discretion will permit one accused to substitute a plea of not guilty and have a trial if for any reason the granting of the privilege seems fair and just. " (Id. at pp. 223-224.) The U.S. Supreme Court in Kercheval reversed the judgment, stating: "The effect of the court's order permitting the withdrawal was to adjudge that the plea of guilty be held for naught. Its subsequent use as evidence against petitioner was in direct conflict with that determination. When the plea was annulled it ceased to be evidence. . . . Giving to the withdrawn plea any weight is in principle quite as inconsistent with the prior order as it would be to hold the plea conclusive. . . . As a practical matter, the guilty plea could not be received as evidence without putting petitioner in a dilemma utterly inconsistent with the determination of the court awarding him a trial. Its introduction may have turned the scale against him. 'The withdrawal of a plea of guilty is a poor privilege, if, notwithstanding its withdrawal, it may be used in evidence under the plea of not guilty.' " (Id. at p. 224.)