OPINION OF THE COURT

Memorandum.

The order of the Appellate Division should be affirmed and the certified question answered in the affirmative.

In this habeas corpus proceeding brought pursuant to Mental Hygiene Law § 33.15, Supreme Court determined that petitioner was no longer mentally ill and ordered his release from custody.1 The Appellate Division agreed with Supreme Court only insofar as it found petitioner to be no longer dangerously mentally ill, but otherwise rejected Supreme Court’s findings and instead found that petitioner was in need of further retention, albeit in a nonsecure facility. We now conclude that the evidence in the record supports the finding of the Appellate Division.

The evidence, adduced through the testimony of petitioner’s treating psychiatrists and that of the chief psychiatrist at the facility where petitioner was institutionalized, as well as through the daily record of petitioner’s behavior, demonstrated that petitioner continued to suffer from a severe *753mental disorder. Even petitioner’s own expert diagnosed petitioner as suffering from "very severe” antisocial and paranoid personality disorders and, like the other experts, recommended that petitioner be retained in some level of custody within the State mental hygiene system.

Mental Hygiene Law § 1.03 (20) defines mental illness as "an affliction with a mental disease or mental condition which is manifested by a disorder or disturbance in behavior, feeling, thinking, or judgment to such an extent that the person afflicted requires care, treatment and rehabilitation.” Contrary to petitioner’s argument, that definition does not exclude disorders such as that suffered by petitioner, solely because "an effective mode of treatment [has] remained elusive” (Matter of Torsney, 47 NY2d 667, 683, n 6). It is enough that petitioner, as every psychiatric expert that testified at the hearing agreed, requires further in-patient care and attention.

Even petitioner’s expert, while objecting to the label "mental illness” to describe petitioner’s condition, agreed with the disposition directed by the Appellate Division. Although that court failed to refer to the governing statutes, its conclusion that petitioner should not be released from in-patient status but should, instead, be transferred to a nonsecure facility as necessary for readjustment to life outside mental hospitals, constitutes the requisite factual findings to justify retaining petitioner under Mental Hygiene Law § 33.15 (b) and § 9.01.2

Finally, contrary to petitioner’s argument, the Appellate *754Division’s reference to "[w]hether petitioner is actually mentally ill” (148 AD2d, at 343) cannot fairly be deemed, within the context of that court’s opinion, to indicate that the court avoided deciding whether petitioner remained "in need of involuntary care and treatment” within the meaning of Mental Hygiene Law § 9.01. Rather, the court was merely acknowledging that petitioner’s current condition would be reviewed on the Commissioner’s pending retention application pursuant to CPL 330.20, as the court itself noted.

(dissenting). I cannot accept the majority’s conclusion that the Appellate Division made the requisite findings under the Mental Hygiene Law to permit the retention of petitioner in a nonsecure facility. Rather, that court determined that petitioner should be retained because even his own expert, who testified that petitioner was not mentally ill, nevertheless favored a gradual release, with some time spent in a nonsecure facility. The court expressly reserved the question of whether petitioner was mentally ill: "While we hold that the trial court’s finding that petitioner is not suffering from a dangerous mental disorder is not against the weight of the evidence, and therefore conclude that petitioner should not be in a secure facility, we disagree with the trial court that he should be released from in-patient status, as opposed to merely transferred to a nonsecure facility. In reaching this result, we think it sufficient that even petitioner’s own expert, a staunch proponent of the view that petitioner is not mentally ill, nevertheless favors only a gradual release, with a period of time spent in a nonsecure facility designed to readjust petitioner to life outside mental hospitals. Whether petitioner is actually mentally ill or not is a question that can be decided on the Commissioner’s pending application for a subsequent retention order, which should now, in view of petitioner’s transfer, be deemed an application for a recommitment order pursuant to CPL 330.20 (14).” (148 AD2d 341, 343 [emphasis added].)

It is clear from this language that the court impermissibly deferred to the Commissioner the determination of whether petitioner presently suffers from a mental illness. To do so in this habeas corpus proceeding pursuant to Mental Hygiene Law § 33.15 (b) was error. That section mandates the release of an involuntarily retained patient upon the court’s finding that the patient "is not mentally disabled or that he is not in *755need of further retention for in-patient care and treatment” (Mental Hygiene Law § 33.15 [b]). A determination that a patient has a "need for retention” requires a showing that the patient is "in need of involuntary care and treatment in a hospital” which in turn requires a demonstration that the patient "has a mental illness” (Mental Hygiene Law § 9.01). As Supreme Court properly concluded, absent a finding that petitioner presently suffers from a mental illness, he is entitled to release.

By concluding that the Appellate Division implicitly found that petitioner suffered from a mental illness, despite that court’s statement to the contrary, the majority deprives petitioner of that court’s factual review of the record — a record upon which Supreme Court, the only other court with fact-finding jurisdiction, found that petitioner was not presently suffering from a mental illness.

Accordingly, I dissent and vote to remit the matter to the Appellate Division for a finding as to whether petitioner presently suffers from a mental illness.

Chief Judge Wachtler and Judges Simons, Kaye, Titone, Hancock, Jr., and Bellacosa concur; Judge Alexander dissents and votes to reverse in an opinion.

Order affirmed, without costs, and certified question answered in the affirmative in a memorandum.