Appellant was charged with robbery, with two prior prison terms alleged, and was held to answer after a preliminary hearing. Prior to trial, the prosecution moved to amend the information by adding a count of petty theft with a prior theft-related offense under Penal Code section 666. Appellant did not object to the amendment, and it was accepted. Appellant was acquitted of the robbery counts, but found guilty of the petty theft. On appeal, he argued that his trial counsel was ineffective for failing to object to the amendment of the information. The appellate court held that the amendment was proper, and therefore there was no ineffective assistance of counsel. Section 666 does not establish a substantive offense, but is a discretionary sentencing statute which allows the court to punish petty theft as either a felony or a misdemeanor. Thus evidence supporting the existence of the prior convictions did not need to be adduced at a preliminary hearing, and section 666 need not be specifically pleaded in the information. Nor was appellant denied due process because the complaint charging robbery put him on notice he could be convicted of the necessarily lesser included offense of petty theft. Further, even if the amendment were improper, counsel could have had a tactical reason for failing to object, such as that he realized that the prosecutor could simply have dismissed and refiled with the new count.