Trial court erred in granting writ of habeas corpus where the petition was untimely and petitioner was no longer in actual or constructive custody. In December of 1997 defendant pled no contest to misdemeanor sexual battery (Pen. Code, §243.4, subd. (d)(1)) for which section 290 registration is required. At the time the present appellate case was decided, defendant had three cases pending for failing to register. In 2010, defendant filed a petition in the superior court to either strike the registration requirement or vacate his plea. Defendant claimed he was not advised at the time he pled that he would be required to register as a sex offender. Finding defendant had not been properly advised, the superior court vacated the 1997 conviction. The prosecution appealed. The Court of Appeal reversed, finding the petition procedurally barred. A petition “must be filed ‘as promptly as the circumstances allow . . . . ‘” Whether there is substantial delay is measured from the time defendant knew or should have known of the legal and factual bases for his claim. Here, defendant signed a form the day after his plea advising him of the registration requirement and was again advised of it when he was released from jail. Defendant failed to show good cause for the substantial delay in filing his claim. Willful ignorance is not good cause for delay. Although the trial court which took defendant’s plea erred when it failed to inform him of the registration requirement, he chose for more than a decade to take no action regarding this error and thereby forfeited his right to contest it. Moreover, defendant’s action is barred by laches as his unreasonable delay prejudiced the prosecution’s ability to answer his petition and to try his case. Finally, pursuant to Penal Code section 1473, subdivision (a), appellant was no longer in actual or constructive custody and therefore could not petition for writ of habeas corpus. The registration requirement does not constitute constructive custody and the cases pending against defendant for failing to register do not revive the case he wishes to challenge.