Ordinarily such a determination is a simple matter of reading the statute. If the defendant is convicted of certain listed crimes, he must register as a sex offender. For out of state convictions, however, a determination must be made. The Board, and Appellate Divisions, had taken the position that this was an administrative determination, which can only be challenged via article 78. My own view was that this was an obvious due process violation, as the defendant's status as a sex offender was determined at a proceeding which denied him notice and an opportunity to be heard (much as the original SORA classification process struck down in People v David W, 95 NY2d 130  [holding that the availability of an Article 78 was insufficient to satisfy the requirements of due process as to the level of classification]). If an article 78 is insufficient to secure the defendant's right to due process regarding what kind of sex offender he is, it seems to me that it is also insufficient to secure the defendant's right to due process regarding whether he is a sex offender at all.
The Court of Appeals today determined that permitting the defendant to challenge - during the SORA classification hearing - the Board's decision that he was required to register was simply a good policy. It held that "A determination by the Board of Examiners of Sex Offenders that a person who committed an offense in another state must register in New York is reviewable in a proceeding to determine the offender's risk level."
It helped that all of the parties agreed that the defendant should not have been required to register, and that he was classified a level three, the highest classification.