In determining the questioned voluntariness of the guilty plea, did the Ninth Circuit impermissibly create confusion when it misapplied the lower standard for competence to stand trial instead of the more demanding Boykin/Ruiz voluntariness analysis to Alvarez's guilty plea?

In determining the voluntariness of a guilty plea, did the Ninth Circuit improperly apply the competence-to-stand-trial standard instead of the Boykin/Ruiz voluntariness analysis?