delivered the opinion of the Court.
Section 320.5(3)(b) of the New York Family Court Act authorizes pretrial detention of an accused juvenile delinquent based on a finding that there is a “serious risk” that the child “may before the return date commit an act which if committed by an adult would constitute a crime.”1 Appellees brought suit on behalf of a class of all juveniles detained pur*256suant to that provision.2 The District Court struck down §320.5(3)(b) as permitting detention without due process of law and ordered the immediate release of all class members. United States ex tel. Martin v. Strasburg, 513 F. Supp. 691 (SDNY 1981). The Court of Appeals for the Second Circuit affirmed, holding the provision “unconstitutional as to all juveniles” because the statute is administered in such a way that “the detention period serves as punishment imposed without proof of guilt established according to the requisite constitutional standard.” Martin v. Strasburg, 689 F. 2d 365, 373-374 (1982). We noted probable jurisdiction, 460 U. S. 1079 (1983),3 and now reverse. We conclude that preventive detention under the FCA serves a legitimate state *257objective, and that the procedural protections afforded pretrial detainees by the New York statute satisfy the requirements of the Due Process Clause of the Fourteenth Amendment to the United States Constitution.
Appellee Gregory Martin was arrested on December 13, 1977, and charged with first-degree robbery, second-degree assault, and criminal possession of a weapon based on an incident in which he, with two others, allegedly hit a youth on the head with a loaded gun and stole his jacket and sneakers. See Petitioners’ Exhibit lb. Martin had possession of the gun when he was arrested. He was 14 years old at the time and, therefore, came within the jurisdiction of New York’s Family Court.4 The incident occurred at 11:30 at night, and Martin lied to the police about where and with whom he lived. He was consequently detained overnight.5
*258A petition of delinquency was filed,6 and Martin made his “initial appearance” in Family Court on December 14th, accompanied by his grandmother.7 The Family Court Judge, citing the possession of the loaded weapon, the false address given to the police, and the lateness of the hour, as evidencing a lack of supervision, ordered Martin detained under §320.5(3)(b) (at that time §739(a)(ii); see n. 2, supra). A probable-cause hearing was held five days later, on December 19th, and probable cause was found to exist for all the crimes charged. At the factfinding hearing held December 27-29, Martin was found guilty on the robbery and criminal possession charges. He was adjudicated a delinquent and *259placed on two years’ probation.8 He had been detained pursuant to § 320.5(3)(b), between the initial appearance and the completion of the factfinding hearing, for a total of 15 days.
Appellees Luis Rosario and Kenneth Morgan, both age 14, were also ordered detained pending their factfinding hearings. Rosario was charged with attempted first-degree robbery and second-degree assault for an incident in which he, with four others, allegedly tried to rob two men, putting a gun to the head of one of them and beating both about the head with sticks. See Petitioners’ Exhibit 2b. At the time of his initial appearance, on March 15, 1978, Rosario had another delinquency petition pending for knifing a student, and two prior petitions had been adjusted.9 Probable cause was *260found on March 21. On April 11, Rosario was released to his father, and the case was terminated without adjustment on September 25, 1978.
Kenneth Morgan was charged with attempted robbery and attempted grand larceny for an incident in which he and another boy allegedly tried to steal money from a 14-year-old girl and her brother by threatening to blow their heads off and grabbing them to search their pockets. See Petitioners’ Exhibit 3b. Morgan, like Rosario, was on release status on another petition (for robbery and criminal possession of stolen property) at the time of his initial appearance on March 27, 1978. He had been arrested four previous times, and his mother refused to come to court because he had been in trouble so often she did not want him home. A probable-cause hearing was set for March 30, but was continued until April 4, when it was combined with a factfinding hearing. Morgan was found guilty of harassment and petit larceny and was ordered placed with the Department of Social Services for 18 months. He was detained a total of eight days between his initial appearance and the factfinding hearing.
On December 21, 1977, while still in preventive detention pending his factfinding hearing, Gregory Martin instituted a *261habeas corpus class action on behalf of “those persons who are, or during the pendency of this action will be, preven-tively detained pursuant to” § 320.5(3)(b) of the FCA. Rosario and Morgan were subsequently added as additional named plaintiffs. These three class representatives sought a declaratory judgment that § 320.5(3)(b) violates the Due Process and Equal Protection Clauses of the Fourteenth Amendment.
In an unpublished opinion, the District Court certified the class. App. 20-32.10 The court also held that appellees were not required to exhaust their state remedies before resorting to federal habeas because the highest state court had already rejected an identical challenge to the juvenile preventive detention statute. See People ex rel. Waybum v. Schupf, 39 N. Y. 2d 682, 350 N. E. 2d 906 (1976). Exhaustion of state remedies, therefore, would be “an exercise in futility.” App. 26.
At trial, appellees offered in evidence the case histories of 34 members of the class, including the three named petitioners. Both parties presented some general statistics on the relation between pretrial detention and ultimate disposition. In addition, there was testimony concerning juvenile proceedings from a number of witnesses, including a legal aid attorney specializing in juvenile cases, a probation supervisor, a child psychologist, and a Family Court Judge. On the basis of this evidence, the District Court rejected the equal protection challenge as “insubstantial,”11 but agreed with appellees that pretrial detention under the FCA violates due process.12 *262The court ordered that “all class members in custody pursuant to Family Court Act Section [320.5(3)(b)] shall be released forthwith.” Id., at 93.
The Court of Appeals affirmed. After reviewing the trial record, the court opined that “the vast majority of juveniles detained under [§ 320.5(3)(b)] either have their petitions dismissed before an adjudication of delinquency or are released after adjudication.” 689 F. 2d, at 369. The court concluded from that fact that § 320.5(3)(b) “is utilized principally, not for preventive purposes, but to impose punishment for unadjudi-cated criminal acts.” Id., at 372. The early release of so many of those detained contradicts any asserted need for pretrial confinement to protect the community. The court therefore concluded that § 320.5(3)(b) must be declared unconstitutional as to all juveniles. Individual litigation would be a practical impossibility because the periods of detention are so short that the litigation is mooted before the merits are determined.13
*263There is no doubt that the Due Process Clause is applicable in juvenile proceedings. “The problem,” we have stressed, “is to ascertain the precise impact of the due process requirement upon such proceedings.” In re Gault, 387 U. S. 1, 13-14 (1967). We have held that certain basic constitutional protections enjoyed by adults accused of crimes also apply to juveniles. See id., at 31-57 (notice of charges, right to counsel, privilege against self-incrimination, right to confrontation and cross-examination); In re Winship, 397 U. S. 358 (1970) (proof beyond a reasonable doubt); Breed v. Jones, 421 U. S. 519 (1975) (double jeopardy). But the Constitution does not mandate elimination of all differences in the treatment of juveniles. See, e. g., McKeiver v. Pennsylvania, 403 U. S. 528 (1971) (no right to jury trial). The State has “a parens patriae interest in preserving and promoting the welfare of the child,” Santosky v. Kramer, 455 U. S. 745, 766 (1982), which makes a juvenile proceeding fundamentally different from an adult criminal trial. We have tried, therefore, to strike a balance — to respect the “informality” and “flexibility” that characterize juvenile proceedings, In re Winship, supra, at 366, and yet to ensure that such proceedings comport with the “fundamental fairness” demanded by the Due Process Clause. Breed v. Jones, supra, at 531; McKeiver, supra, at 543 (plurality opinion).
The statutory provision at issue in these cases, § 320.5(3)(b), permits a brief pretrial detention based on a finding of a “serious risk” that an arrested juvenile may commit a crime before his return date. The question before us is whether preventive detention of juveniles pursuant to §320.5(3)(b) is compatible with the “fundamental fairness” required by due process. Two separate inquiries are necessary to answer this question. First, does preventive detention under the *264New York statute serve a legitimate state objective? See Bell v. Wolfish, 441 U. S. 520, 534, n. 15 (1979); Kennedy v. Mendoza-Martinez, 372 U. S. 144, 168-169 (1963). And, second, are the procedural safeguards contained in the FCA adequate to authorize the pretrial detention of at least some juveniles charged with crimes? See Mathews v. Eldridge, 424 U. S. 319, 335 (1976); Gerstein v. Pugh, 420 U. S. 103, 114 (1975).
A
Preventive detention under the FCA is purportedly designed to protect the child and society from the potential consequences of his criminal acts. People ex rel. Wayburn v. Schupf, 39 N. Y. 2d, at 689-690, 350 N. E. 2d, at 910. When making any detention decision, the Family Court judge is specifically directed to consider the needs and best interests of the juvenile as well as the need for the protection of the community. FCA §301.1; In re Craig S., 57 App. Div. 2d 761, 394 N. Y. S. 2d 200 (1977). In Bell v. Wolfish, supra, at 534, n. 15, we left open the question whether any governmental objective other than ensuring a detainee’s presence at trial may constitutionally justify pretrial detention. As an initial matter, therefore, we must decide whether, in the context of the juvenile system, the combined interest in protecting both the community and the juvenile himself from the consequences of future criminal conduct is sufficient to justify such detention.
The “legitimate and compelling state interest” in protecting the community from crime cannot be doubted. De Veau v. Braisted, 363 U. S. 144, 155 (1960). See also Terry v. Ohio, 392 U. S. 1, 22 (1968). We have stressed before that crime prevention is “a weighty social objective,” Brown v. Texas, 443 U. S. 47, 52 (1979), and this interest persists undiluted in the juvenile context. See In re Gault, supra, at 20, n. 26. The harm suffered by the victim of a crime is not de*265pendent upon the age of the perpetrator.14 And the harm to society generally may even be greater in this context given the high rate of recidivism among juveniles. In re Gault, supra, at 22.
The juvenile’s countervailing interest in freedom from institutional restraints, even for the brief time involved here, is undoubtedly substantial as well. See In re Gault, supra, at 27. But that interest must be qualified by the recognition that juveniles, unlike adults, are always in some form of custody. Lehman v. Lycoming County Children’s Services, 458 U. S. 502, 510-511 (1982); In re Gault, supra, at 17. Children, by definition, are not assumed to have the capacity to take care of themselves. They are assumed to be subject to the control of their parents, and if parental control falters, the State must play its part as parens patriae. See State v. Gleason, 404 A. 2d 573, 580 (Me. 1979); People ex rel. Waybum v. Schupf, supra, at 690, 350 N. E. 2d, at 910; Baker v. Smith, 477 S. W. 2d 149, 150-151 (Ky. App. 1971). In this respect, the juvenile’s liberty interest may, in appropriate circumstances, be subordinated to the State’s “parens patriae interest in preserving and promoting the welfare of the child.” Santosky v. Kramer, supra, at 766.
The New York Court of Appeals, in upholding the statute at issue here, stressed at some length “the desirability of protecting the juvenile from his own folly.” People ex rel. Wayburn v. Schupf, supra, at 688-689, 350 N. E. 2d, at 909.16 *266Society has a legitimate interest in protecting a juvenile from the consequences of his criminal activity — both from potential physical injury which may be suffered when a victim fights back or a policeman attempts to make an arrest and from the downward spiral of criminal activity into which peer pressure may lead the child. See L. O. W. v. District Court of Arapahoe, 623 P. 2d 1253, 1258-1259 (Colo. 1981); Morris v. D’Amario, 416 A. 2d 137, 140 (R. I. 1980). See also Eddings v. Oklahoma, 455 U. S. 104, 115 (1982) (minority “is a time and condition of life when a person may be most susceptible to influence and to psychological damage”); Bellotti v. Baird, 443 U. S. 622, 635 (1979) (juveniles “often lack the experience, perspective, and judgment to recognize and avoid choices that could be detrimental to them”).
The substantiality and legitimacy of the state interests underlying this statute are confirmed by the widespread use and judicial acceptance of preventive detention for juveniles. Every State, as well as the United States in the District of *267Columbia, permits preventive detention of juveniles accused of crime.16 A number of model juvenile justice Acts also contain provisions permitting preventive detention.17 And the *268courts of eight States, including the New York Court of Appeals, have upheld their statutes with specific reference to protecting the juvenile and the community from harmful pretrial conduct, including pretrial crime. L. O. W. v. District Court of Arapahoe, supra, at 1258-1259; Morris v. D’Amario, supra, at 139-140; State v. Gleason, 404 A. 2d, at 583; Pauley v. Gross, 1 Kan. App. 2d 736, 738-740, 574 P. 2d 234, 237-238 (1977); People ex rel. Wayburn v. Schupf, 39 N. Y. 2d, at 688-689, 350 N. E. 2d, at 909-910; Aubrey v. Gadbois, 50 Cal. App. 3d 470, 472, 123 Cal. Rptr. 365, 366 (1975); Baker v. Smith, 477 S. W. 2d, at 150-151; Commonwealth ex rel. Sprowal v. Hendrick, 438 Pa. 435, 438-439, 265 A. 2d 348, 349-350 (1970).
“The fact that a practice is followed by a large number of states is not conclusive in a decision as to whether that practice accords with due process, but it is plainly worth considering in determining whether the practice ‘offends some principle of justice so rooted in the traditions and conscience of our people as to be ranked as fundamental.’ Snyder v. Massachusetts, 291 U. S. 97, 105 (1934).” Leland v. Oregon, 343 U. S. 790, 798 (1952). In light of the uniform legislative judgment that pretrial detention of juveniles properly promotes the interests both of society and the juvenile, we conclude that the practice serves a legitimate regulatory purpose compatible with the “fundamental fairness” demanded by the Due Process Clause in juvenile proceedings. Cf. McKeiver v. Pennsylvania, 403 U. S., at 548 (plurality opinion).18
*269Of course, the mere invocation of a legitimate purpose will not justify particular restrictions and conditions of confinement amounting to punishment. It is axiomatic that “[d]ue process requires that a pretrial detainee not be punished.” Bell v. Wolfish, 441 U. S., at 535, n. 16. Even given, therefore, that pretrial detention may serve legitimate regulatory purposes, it is still necessary to determine whether the terms and conditions of confinement under § 320.5(3)(b) are in fact compatible with those purposes. Kennedy v. Mendoza-Martinez, 372 U. S., at 168-169. “A court must decide whether the disability is imposed for the purpose of punishment or whether it is but an incident of some other legitimate governmental purpose.” Bell v. Wolfish, supra, at 538. Absent a showing of an express intent to punish on the part of the State, that determination generally will turn on “whether an alternative purpose to which [the restriction] may rationally be connected is assignable for it, and whether it appears excessive in relation to the alternative purpose assigned [to it].” Kennedy v. Mendoza-Martinez, supra, at 168-189. See Bell v. Wolfish, supra, at 538; Flemming v. Nestor, 363 U. S. 603, 613-614 (1960).
There is no indication in the statute itself that preventive detention is used or intended as a punishment. First of all, the detention is strictly limited in time. If a juvenile is detained at his initial appearance and has denied the charges *270against him, he is entitled to a probable-cause hearing to be held not more than three days after the conclusion of the initial appearance or four days after the filing of the petition, whichever is sooner. FCA § 325.1(2).19 If the Family Court judge finds probable cause, he must also determine whether continued detention is necessary pursuant to §320.5(3Xb). §325.3(3).
Detained juveniles are also entitled to an expedited factfinding hearing. If the juvenile is charged with one of a limited number of designated felonies, the factfinding hearing must be scheduled to commence not more than 14 days after the conclusion of the initial appearance. §340.1. If the juvenile is charged with a lesser offense, then the factfinding hearing must be held not more than three days after the initial appearance.20 In the latter case, since the times for the probable-cause hearing and the factfinding hearing coincide, the two hearings are merged.
Thus, the maximum possible detention under §320.5(3)(b) of a youth accused of a serious crime, assuming a 3-day extension of the factfinding hearing for good cause shown, is 17 days. The maximum detention for less serious crimes, again assuming a 3-day extension for good cause shown, is six days. These time frames seem suited to the limited purpose of providing the youth with a controlled environment and separating him from improper influences pending the speedy disposition of his case.
The conditions of confinement also appear to reflect the regulatory purposes relied upon by the State. When a juvenile is remanded after his initial appearance, he cannot, absent exceptional circumstances, be sent to a prison or lockup where he would be exposed to adult criminals. FCA *271§ 304.1(2). Instead, the child is screened by an “assessment unit” of the Department of Juvenile Justice. Testimony of Mr. Kelly (Deputy Commissioner of Operations, New York City Department of Juvenile Justice), App. 286-287. The assessment unit places the child in either nonsecure or secure detention. Nonsecure detention involves an open facility in the community, a sort of “halfway house,” without locks, bars, or security officers where the child receives schooling and counseling and has access to recreational facilities. Id., at 285; Testimony of Mr. Benjamin, id., at 149-150.
Secure detention is more restrictive, but it is still consistent with the regulatory and parens patriae objectives relied upon by the State. Children are assigned to separate dorms based on age, size, and behavior. They wear street clothes provided by the institution and partake in educational and recreational programs and counseling sessions run by trained social workers. Misbehavior is punished by confinement to one’s room. See Testimony of Mr. Kelly, id., at 292-297. We cannot conclude from this record that the controlled environment briefly imposed by the State on juveniles in secure pretrial detention “is imposed for the purpose of punishment” rather than as “an incident of some other legitimate governmental purpose.” Bell v. Wolfish, 441 U. S., at 538.
The Court of Appeals, of course, did conclude that the underlying purpose of §320.5(3)(b) is punitive rather than regulatory. But the court did not dispute that preventive detention might serve legitimate regulatory purposes or that the terms and conditions of pretrial confinement in New York are compatible with those purposes. Rather, the court invalidated a significant aspect of New York’s juvenile justice system based solely on some case histories and a statistical study which appeared to show that “the vast majority of juveniles detained under [§320.5(3)(b)] either have their petitions dismissed before an adjudication of delinquency or are released after adjudication.” 689 F. 2d, at 369. The court assumed that dismissal of a petition or failure to confine a juvenile at *272the dispositional hearing belied the need to detain him prior to factfinding and that, therefore, the pretrial detention constituted punishment. Id., at B73. Since punishment imposed without a prior adjudication of guilt is per se illegitimate, the Court of Appeals concluded that no juveniles could be held pursuant to §320.5(3)(b).
There are some obvious flaws in the statistics and case histories relied upon by the lower court.21 But even assuming it to be the case that “by far the greater number of juveniles incarcerated under [§320.5(3)(b)] will never be confined as a consequence of a disposition imposed after an adjudication of delinquency,” 689 F. 2d, at 371-372, we find that to be an insufficient ground for upsetting the widely shared legislative judgment that preventive detention serves an important and legitimate function in the juvenile justice system. We are unpersuaded by the Court of Appeals’ rather cavalier equation of detentions that do not lead to continued confinement after an adjudication of guilt and “wrongful” or “punitive” pretrial detentions.
Pretrial detention need not be considered punitive merely because a juvenile is subsequently discharged subject to con*273ditions or put on probation. In fact, such actions reinforce the original finding that close supervision of the juvenile is required. Lenient but supervised disposition is in keeping with the Act’s purpose to promote the welfare and development of the child.22 As the New York Court of Appeals noted:
“It should surprise no one that caution and concern for both the juvenile and society may indicate the more conservative decision to detain at the very outset, whereas the later development of very much more relevant information may prove that while a finding of delinquency was warranted, placement may not be indicated.” People ex rel. Wayburn v. Schupf, 39 N. Y. 2d, at 690, 350 N. E. 2d, at 910.
Even when a case is terminated prior to factfinding, it does not follow that the decision to detain the juvenile pursuant to § 320.5(3)(b) amounted to a due process violation. A delinquency petition may be dismissed for any number of reasons collateral to its merits, such as the failure of a witness to testify. The Family Court judge cannot be expected to anticipate such developments at the initial hearing. He makes his decision based on the information available to him at that time, and the propriety of the decision must be judged in that light. Consequently, the final disposition of a case is “largely irrelevant” to the legality of a pretrial detention. Baker v. McCollan, 443 U. S. 137, 145 (1979).
It may be, of course, that in some circumstances detention of a juvenile would not pass constitutional muster. But the validity of those detentions must be determined on a case-by-ease basis. Section 320.5(3)(b) is not invalid “on its face” by *274reason of the ambiguous statistics and case histories relied upon by the court below.23 We find no justification for the conclusion that, contrary to the express language of the statute and the judgment of the highest state court, §320.5(3)(b) is a punitive rather than a regulatory measure. Preventive detention under the FCA serves the legitimate state objective, held in common with every State in the country, of protecting both the juvenile and society from the hazards of pretrial crime.
B
Given the legitimacy of the State’s interest in preventive detention, and the nonpunitive nature of that detention, the remaining question is whether the procedures afforded juveniles detained prior to factfinding provide sufficient protection against erroneous and unnecessary deprivations of liberty. See Mathews v. Eldridge, 424 U. S., at 335.24 In Gerstein v. Pugh, 420 U. S., at 114, we held that a judicial *275determination of probable cause is a prerequisite to any extended restraint on the liberty of an adult accused of crime. We did not, however, mandate a specific timetable. Nor did we require the “full panoply of adversary safeguards — counsel, confrontation, cross-examination, and compulsory process for witnesses.” Id., at 119. Instead, we recognized “the desirability of flexibility and experimentation by the States.” Id., at 123. Gerstein arose under the Fourth Amendment, but the same concern with “flexibility” and “informality,” while yet ensuring adequate predetention procedures, is present in this context. In re Winship, 397 U. S., at 366; Kent v. United States, 383 U. S. 541, 554 (1966).
In many respects, the FCA provides far more predetention protection for juveniles than we found to be constitutionally required for a probable-cause determination for adults in Gerstein. The initial appearance is informal, but the accused juvenile is given full notice of the charges against him and a complete stenographic record is kept of the hearing. See 513 F. Supp., at 702. The juvenile appears accompanied by his parent or guardian.25 He is first informed of his rights, including the right to remain silent and the right to be represented by counsel chosen by him or by a law guardian assigned by the court. FCA §320.3. The initial appearance may be adjourned for no longer than 72 hours or until the next court day, whichever is sooner, to enable an appointed law guardian or other counsel to appear before the court. §320.2(3). When his counsel is present, the juvenile is informed of the charges against him and furnished with.a copy of the delinquency petition. §320.4(1). A representative from the presentment agency appears in support of the petition.
The nonhearsay allegations in the delinquency petition and supporting depositions must establish probable cause to *276believe the juvenile committed the offense. Although the Family Court judge is not required to make a finding of probable cause at the initial appearance, the youth may challenge the sufficiency of the petition on that ground. FCA § 315.1. Thus, the juvenile may oppose any recommended detention by arguing that there is not probable cause to believe he committed the offense or offenses with which he is charged. If the petition is not dismissed, the juvenile is given an opportunity to admit or deny the charges. §321.1.26
At the conclusion of the initial appearance, the presentment agency makes a recommendation regarding detention. A probation officer reports on the juvenile’s record, including other prior and current Family Court and probation contacts, as well as relevant information concerning home life, school attendance, and any special medical or developmental problems. He concludes by offering his agency’s recommendation on detention. Opposing counsel, the juvenile’s parents, and the juvenile himself may all speak on his behalf and challenge any information or recommendation. If the judge does decide to detain the juvenile under §320.5(3)(b), he must state on the record the facts and reasons for the detention.27
*277As noted, a detained juvenile is entitled to a formal, adversarial probable-cause hearing within three days of his initial appearance, with one 3-day extension possible for good cause shown.28 The burden at this hearing is on the presentment agency to call witnesses and offer evidence in support of the charges. §325.2. Testimony is under oath and subject to cross-examination. Ibid. The accused juvenile may call witnesses and offer evidence in his own behalf. If the court finds probable cause, the court must again decide whether continued detention is necessary under § 320.5(3)(b). Again, the facts and reasons for the detention must be stated on the record.
In sum, notice, a hearing, and a statement of facts and reasons are given prior to any detention under § 320.5(3)(b). A formal probable-cause hearing is then held within a short while thereafter, if the factfinding hearing is not itself scheduled within three days. These flexible procedures have been found constitutionally adequate under the Fourth Amendment, see Gerstein v. Pugh, and under the Due Process Clause, see Kent v. United States, supra, at 557. Appellees have failed to note any additional procedures that would significantly improve the accuracy of the determination without unduly impinging on the achievement of legitimate state purposes.29
*278Appellees argue, however, that the risk of erroneous and unnecessary detentions is too high despite these procedures because the standard for detention is fatally vague. Detention under §320.5(3)(b) is based on a finding that there is a “serious risk” that the juvenile, if released, would commit a crime prior to his next court appearence. We have already seen that detention of juveniles on that ground serves legitimate regulatory purposes. But appellees claim, and the District Court agreed, that it is virtually impossible to predict future criminal conduct with any degree of accuracy. Moreover, they say, the statutory standard fails to channel the discretion of the Family Court judge by specifying the factors on which he should rely in making that prediction. The procedural protections noted above are thus, in their view, unavailing because the ultimate decision is intrinsically arbitrary and uncontrolled.
Our cases indicate, however, that from a legal point of view there is nothing inherently unattainable about a prediction of future criminal conduct. Such a judgment forms an important element in many decisions,30 and we have specifically re*279jected the contention, based on the same sort of sociological data relied upon by appellees and the District Court, “that it is impossible to predict future behavior and that the question is so vague as to be meaningless.” Jurek v. Texas, 428 U. S. 262, 274 (1976) (opinion of Stewart, Powell, and Stevens, JJ.); id., at 279 (White, J., concurring in judgment).
We have also recognized that a prediction of future criminal conduct is “an experienced prediction based on a host of variables” which cannot be readily codified. Greenholtz v. Nebraska Penal Inmates, 442 U. S. 1, 16 (1979). Judge Qui-nones of the Family Court testified at trial that he and his colleagues make a determination under § 320.5(3)(b) based on numerous factors including the nature and seriousness of the charges; whether the charges are likely to be proved at trial; the juvenile’s prior record; the adequacy and effectiveness of his home supervision; his school situation, if known; the time of day of the alleged crime as evidence of its seriousness and a possible lack of parental control; and any special circumstances that might be brought to his attention by the probation officer, the child’s attorney, or any parents, relatives, or other responsible persons accompanying the child. Testimony of Judge Quinones, App. 254-267. The decision is based on as much information as can reasonably be obtained at the initial appearance. Ibid.
Given the right to a hearing, to counsel, and to a statement of reasons, there is no reason that the specific factors upon which the Family Court judge might rely must be specified in the statute. As the New York Court of Appeals concluded, People ex rel. Wayburn v. Schupf, 39 N. Y. 2d, at 690, 350 N. E. 2d, at 910, “to a very real extent Family Court must exercise a substitute parental control for which there can be *280no particularized criteria.” There is also no reason, we should add, for a federal court to assume that a state court judge will not strive to apply state law as conscientiously as possible. Sumner v. Mata, 449 U. S. 539, 549 (1981).
It is worth adding that the Court of Appeals for the Second Circuit was mistaken in its conclusion that “[ijndividual litigation ... is a practical impossibility because the periods of detention are so short that the litigation is mooted before the merits are determined.” 689 F. 2d, at 373. In fact, one of the juveniles in the very case histories upon which the court relied was released from pretrial detention on a writ of ha-beas corpus issued by the State Supreme Court. New York courts also have adopted a liberal view of the doctrine of “capable of repetition, yet evading review” precisely in order to ensure that pretrial detention orders are not unre viewable. In People ex rel. Wayburn v. Schupf, supra, at 686, 350 N. E. 2d, at 908, the court declined to dismiss an appeal from the grant of a writ of habeas corpus despite the technical mootness of the case.
“Because the situation is likely to recur . . . and the substantial issue may otherwise never be reached (in view of the predictably recurring happenstance that, however expeditiously an appeal might be prosecuted, fact-finding and dispositional hearings normally will have been held and a disposition made before the appeal could reach us), ... we decline to dismiss [the appeal] on the ground of mootness.”
The required statement of facts and reasons justifying the detention and the stenographic record of the initial appearance will provide a basis for the review of individual cases. Pretrial detention orders in New York may be reviewed by writ of habeas corpus brought in State Supreme Court. And the judgment of that court is appealable as of right and may be taken directly to the Court of Appeals if a constitutional question is presented. N. Y. Civ. Prac. Law § 5601(b)(2) *281(McKinney 1978). Permissive appeal from a Family Court order may also be had to the Appellate Division. FCA §365.2. Or a motion for reconsideration may be directed to the Family Court judge. §355.1(l)(b). These post-detention procedures provide a sufficient mechanism for correcting on a case-by-case basis any erroneous detentions ordered under §320.5(3). Such procedures may well flesh out the standards specified in the statute.
p — i I ! — I
The dissent would apparently have us strike down New York’s preventive detention statute on two grounds: first, because the preventive detention of juveniles constitutes poor public policy, with the balance of harms outweighing any positive benefits either to society or to the juveniles themselves, post, at 290-291, 308, and, second, because the statute could have been better drafted to improve the quality of the decisionmaking process, post, at 304-306. But it is worth recalling that we are neither a legislature charged with formulating public policy nor an American Bar Association committee charged with drafting a model statute. The question before us today is solely whether the preventive detention system chosen by the State of New York and applied by the New York Family Court comports with constitutional standards. Given the regulatory purpose for the detention and the procedural protections that precede its imposition, we conclude that § 320.5(3)(b) of the New York FCA is not invalid under the Due Process Clause of the Fourteenth Amendment.
The judgment of the Court of Appeals is
Reversed.
New York Jud. Law § 320.5 (McKinney 1983) (Family Court Act (hereinafter FCA)) provides, in relevant part:
“1. At the initial appearance, the court in its discretion may release the respondent or direct his detention.
“3. The court shall not direct detention unless it finds and states the facts and reasons for so finding that unless the respondent is detained;
“(a) there is a substantial probability that he will not appear in court on the return date; or
“(b) there is a serious risk that he may before the return date commit an act which if committed by an adult would constitute a crime.”
Appellees have only challenged pretrial detention under § 320.5(3)(b). Thus, the propriety of detention to ensure that a juvenile appears in court on the return date, pursuant to § 320.5(3)(a), is not before the Court.
The original challenge was to § 739(a)(ii) of the FCA, which, at the time of the commencement of this suit, governed pretrial release or detention of both alleged juvenile delinquents and persons in need of supervision. Effective July 1, 1983, a new Article 3 to the Act governs, inter alia, “all juvenile delinquency actions and proceedings commenced upon or after the effective date thereof and all appeals and other post-judgment proceedings relating or attaching thereto.” FCA §301.3(1). Article 7 now applies only to proceedings concerning persons in need of supervision.
Obviously, this Court must “review the judgment below in light of the . . . statute as it now stands, not as it once did.” Hall v. Beals, 396 U. S. 45, 48 (1969). But since new Article 3 contains a preventive detention section identical to former §739(a)(ii), see FCA §320.5(3), the appeal is not moot. Brockington v. Rhodes, 396 U. S. 41, 43 (1969).
Although the pretrial detention of the class representatives has long since ended, see infra, at 257-261, this case is not moot for the same reason that the class action in Gerstein v. Pugh, 420 U. S. 103, 110, n. 11 (1975), was not mooted by the termination of the claims of the named plaintiffs. “Pretrial detention is by nature temporary, and it is most unlikely that any given individual could have his constitutional claim decided on appeal before he is either released or convicted. The individual could nonetheless suffer repeated deprivations, and it is certain that other persons similarly situated will be detained under the allegedly unconstitutional procedures. The claim, in short, is one that is distinctly ‘capable of repetition, yet evading review.’”
See also People ex rel. Wayburn v. Schupf, 39 N. Y. 2d 682, 686-687, 350 N. E. 2d 906, 907-908 (1976).
In New York, a child over the age of 7 but less than 16 is not considered criminally responsible for his conduct. FCA §301.2(1). If he commits an act that would constitute a crime if committed by an adult, he comes under the exclusive jurisdiction of the Family Court. §302.1(1). That court is charged not with finding guilt and affixing punishment, In re Bogart, 45 Mise. 2d 1075, 259 N. Y. S. 2d 351 (1963), but rather with determining and pursuing the needs and best interests of the child insofar as those are consistent with the need for the protection of the community. FCA § 301.1. See In re Craig S., 57 App. Div. 2d 761, 394 N. Y. S. 2d 200 (1977). Juvenile proceedings are, thus, civil rather than criminal, although because of the restrictions that may be placed on a juvenile adjudged delinquent, some of the same protections afforded accused adult criminals are also applicable in this context. Cf. FCA § 303.1.
When a juvenile is arrested, the arresting officer must immediately notify the parent or other person legally responsible for the child’s care. FCA § 305.2(3). Ordinarily, the child will be released into the custody of his parent or guardian after being issued an “appearance ticket” requiring him to meet with the probation service on a specified day. §307.1(1). See n. 9, infra. If, however, he is charged with a serious crime, one of several designated felonies, see § 301.2(8), or if his parent or guardian cannot be reached, the juvenile may be taken directly before the Family Court. § 305.2. The Family Court judge will make a preliminary deter*258mination as to the jurisdiction of the court, appoint a law guardian for the child, and advise the child of his or her rights, including the right to counsel and the right to remain silent.
Only if, as in Martin’s case, the Family Court is not in session and special circumstances exist, such as an inability to notify the parents, will the child be taken directly by the arresting officer to a juvenile detention facility. § 305.2(4)(c). If the juvenile is so detained, he must be brought before the Family Court within 72 hours or the next day the court is in session, whichever is sooner. § 307.3(4). The propriety of such detention, prior to a juvenile’s initial appearance in Family Court, is not at issue in this case. Appellees challenged only judicially ordered detention pursuant to § 320.5(3)(b).
A delinquency petition, prepared by the “presentment agency,” originates delinquency proceedings. FCA § 310.1. The petition must contain, inter alia, a precise statement of each crime charged and factual allegations which “clearly apprise” the juvenile of the conduct which is the subject of the accusation. §311.1. A petition is not deemed sufficient unless the allegations of the factual part of the petition, together with those of any supporting depositions which may accompany it, provide reasonable cause to believe that the juvenile committed the crime or crimes charged. §311.2(2). Also, nonhearsay allegations in the petition and supporting deposition must establish, if true, every element of each crime charged and the juvenile’s commission thereof. § 311.2(3). The sufficiency of a petition may be tested by filing a motion to dismiss under § 315.1.
The first proceeding in Family Court following the filing of the petition is known as the initial appearance even if the juvenile has already been brought before the court immediately following his arrest. FCA § 320.2.
The “factfinding” is the juvenile’s analogue of a trial. As in the earlier proceedings, the juvenile has a right to counsel at this hearing. § 341.2. See In re Gault, 387 U. S. 1 (1967). Evidence may be suppressed on the same grounds as in criminal cases, FCA § 330.2, and proof of guilt, based on the record evidence, must be beyond a reasonable doubt, § 342.2. See In re Winship, 397 U. S. 358 (1970). If guilt is established, the court enters an appropriate order and schedules a dispositional hearing. § 345.1.
The dispositional hearing is the final and most important proceeding in the Family Court. If the juvenile has committed a designated felony, the court must order a probation investigation and a diagnostic assessment. § 351.1. Any other material and relevant evidence may be offered by the probation agency or the juvenile. Both sides may call and cross-examine witnesses and recommend specific dispositional alternatives. §350.4. The court must find, based on a preponderance of the evidence, § 350.3(2), that the juvenile is delinquent and requires supervision, treatment, or confinement. §352.1. Otherwise, the petition is dismissed. Ibid.
If the juvenile is found to be delinquent, then the court enters an order of disposition. Possible alternatives include a conditional discharge; probation for up to two years; nonsecure placement with, perhaps, a relative or the Division for Youth; transfer to the Commissioner of Mental Health; or secure placement. §§ 353.1-353.5. Unless the juvenile committed one of the designated felonies, the court must order the least restrictive available alternative consistent with the needs and best interests of the juvenile and the need for protection of the community. § 352.2(2).
Every accused juvenile is interviewed by a member of the staff of the Probation Department. This process is known as “probation intake.” See *260Testimony of Mr. Benjamin (Supervisor, New York Dept, of Probation), App. 142. In the course of the interview, which lasts an average of 45 minutes, the probation officer will gather what information he can about the nature of the case, the attitudes of the parties involved, and the child’s past history and current family circumstances. Id,., at 144, 153. His sources of information are the child, his parent or guardian, the arresting officer, and any records of past contacts between the child and the Family Court. On the basis of this interview, the probation officer may attempt to “adjust,” or informally resolve, the case. FCA § 308.1(2). Adjustment is a purely voluntary process in which the complaining witness agrees not to press the case further, while the juvenile is given a warning or agrees to counseling sessions or, perhaps, referral to a community agency. § 308.1 (Practice Commentary). In cases involving designated felonies or other serious crimes, adjustment is not permitted without written approval of the Family Court. §308.1(4). If a case is not informally adjusted, it is referred to the “presentment agency.” See n. 6, supra.
We have never decided whether Federal Rule of Civil Procedure 23, providing for class actions, is applicable to petitions for habeas corpus relief. See Bell v. Wolfish, 441 U. S. 520, 527, n. 6 (1979); Middendorf v. Henry, 425 U. S. 25, 30 (1976). Although appellants contested the class certification in the District Court, they did not raise the issue on appeal; nor do they urge it here. Again, therefore, we have no occasion to reach the question.
The equal protection claim, which was neither raised on appeal nor decided by the Second Circuit, is not before us.
The District Court gave three reasons for this conclusion. First, under the FCA, a juvenile may be held in pretrial detention for up to five *262days without any judicial determination of probable cause. Relying on Gerstein v. Pugh, 420 U. S., at 114, the District Court concluded that pretrial detention without a prior adjudication of probable cause is, itself, a per se violation of due process. United States ex rel. Martin v. Strasburg, 513 F. Supp. 691, 717 (SDNY 1981).
Second, after a review of the pertinent scholarly literature, the court noted that “no diagnostic tools have as yet been devised which enable even the most highly trained criminologists to predict reliably which juveniles will engage in violent crime.” Id., at 708. A fortiori, the court concluded, a Family Court judge cannot make a reliable prediction based on the limited information available to him at the initial appearance. Id., at 712. Moreover, the court felt that the trial record was “replete” with examples of arbitrary and capricious detentions. Id., at 713.
Finally, the court concluded that preventive detention is merely a euphemism for punishment imposed without an adjudication of guilt. The alleged purpose of the detention' — to protect society from the juvenile’s criminal conduct — is indistinguishable from the purpose of post-trial detention. And given “the inability of trial judges to predict which juveniles will commit crimes,” there is no rational connection between the decision to detain and the alleged purpose, even if that purpose were legitimate. Id., at 716.
Judge Newman concurred separately. He was not convinced that the record supported the majority’s statistical conclusions. But he thought *263that the statute was procedurally infirm because it granted unbridled discretion to Family Court judges to make an inherently uncertain prediction of future criminal behavior. 689 F. 2d, at 377.
In 1982, juveniles under 16 accounted for 7.5 percent of all arrests for violent crimes, 19.9 percent of all arrests for serious property crime, and 17.3 percent of all arrests for violent and serious property crimes combined. U. S. Dept, of Justice, Federal Bureau of Investigation, Crime in the United States 176-177 (1982) (“violent crimes” include murder, non-negligent manslaughter, forcible rape, robbery, and aggravated assault; “serious property crimes” include burglary, larceny-theft, motor vehicle theft, and arson).
“Our society recognizes that juveniles in general are in the earlier stages of their emotional growth, that their intellectual development is *266incomplete, that they have had only limited practical experience, and that their value systems have not yet been clearly identified or firmly adopted. . . .
“For the same reasons that our society does not hold juveniles to an adult standard of responsibility for their conduct, our society may also conclude that there is a greater likelihood that a juvenile charged with delinquency, if released, will commit another criminal act than that an adult charged with crime will do so. To the extent that self-restraint may be expected to constrain adults, it may not be expected to operate with equal force as to juveniles. Because of the possibility of juvenile delinquency treatment and the absence of second-offender sentencing, there will not be the deterrent for the juvenile which confronts the adult. Perhaps more significant is the fact that in consequence of lack of experience and comprehension the juvenile does not view the commission of what are criminal acts in the same perspective as an adult. . . . There is the element of gamesmanship and the excitement of ‘getting away’ with something and the powerful inducement of peer pressures. All of these commonly acknowledged factors make the commission of criminal conduct on the part of juveniles in general more likely than in the case of adults.” People ex rel. Wayburn v. Sckupf, 39 N. Y. 2d, at 687-688, 350 N. E. 2d, at 908-909.
Ala. Code § 12-15-59 (1975); Alaska Stat. Ann. § 47.10.140 (1979); Rule 3, Ariz. Juv. Ct. Rules of Proc., Ariz. Rev. Stat. Ann. (Supp. 1983-1984 to vol. 17A); Ark. Stat. Ann. §45-421 (Supp. 1983); Cal. Welf. & Inst. Code Ann. § 628 (West Supp. 1984); Colo. Rev. Stat. § 19-2-102 (Supp. 1983); Conn. Gen. Stat. §46b-131 (Supp. 1984); Del. Fam. Ct. Rule 60 (1981); D. C. Code §16-2310 (1981); Fla. Stat. §39.032 (Supp. 1984); Ga. Code Ann. §15-11-19 (1982); Haw. Rev. Stat. §571-31.1 (Supp. 1984); Idaho Code §16-1811 (Supp. 1983); Ill. Rev. Stat., ch. 37, §703-4 (1983); Ind. Code §31-6-4-5 (1982); Iowa Code §232.22 (1983); Kan. Stat. Ann. §38-1632 (Supp. 1983); Ky. Rev. Stat. §208.192 (1982); La. Code Juv. Proc. Ann., Art. 40 (West 1983 Pamphlet); Me. Rev. Stat. Ann., Tit. 15, §3203 (1964 and Supp. 1983-1984); Md. Cts. & Jud. Proc. Code Ann. §3-815 (1984); Mass. Gen. Laws Ann., ch. 119, §66 (West Supp. 1983-1984); Mich. Comp. Laws §712A.15 (1979); Minn. Stat. §260.171 (1982); Miss. Code Ann. § 43-23-11 (1972); Mo. Juv. Ct. Rule 111.02 (1981); Mont. Code Ann. §41-5-305 (1983); Neb. Rev. Stat. §43-255 (Supp. 1982); Nev. Rev. Stat. §62.140 (1983); N. H. Rev. Stat. Ann. §169B:14 (Supp. 1983); N. J. Stat. Ann. §2A:4-56 (Supp. 1983-1984); N. M. Stat. Ann. §32-1-24 (1981); N. Y. FCA §320.5(3) (McKinney 1983); N. C. Gen. Stat. § 7A-574 (Supp. 1983); N. D. Cent. Code §27-20-14 (1974); Ohio Rev. Code Ann. §2151.311 (1976); Okla. Stat., Tit. 10, § 1107 (Supp. 1983); Ore. Rev. Stat. §419.573 (1983); 42 Pa. Cons. Stat. §6325 (1982); R. I. Gen. Laws §§14-1-20, 14-1-21 (1981); S. C. Code §20-7-600 (Supp. 1983); S. D. Codified Laws § 26-8-19.2 (Supp. 1983); Tenn. Code Ann. § 37-1-114 (1984); Tex. Fam. Code Ann. § 53.02 (1975 and Supp. 1984); Utah Code Ann. §78-3a-30 (Supp. 1983); Vt. Stat. Ann., Tit. 33, §643 (1981); Va. Code § 16.1-248 (1982); Wash. Rev. Code § 13.40.040 (1983); W. Va. Code §49-5-8 (Supp. 1983); Wis. Stat. §48.208 (1981-1982); Wyo. Stat. § 14-6-206 (1977).
See U. S. Dept, of Justice, Office of Juvenile Justice and Delinquency Prevention, Standards for the Administration of Juvenile Justice, Report of the National Advisory Committee for Juvenile Justice and Delinquency Prevention 294-296 (July 1980); Uniform Juvenile Court Act § 14, 9A U. L. A. 22 (1979); Standard Juvenile Court Act, Art. IV, § 16, proposed by the National Council on Crime and Delinquency (1959); W. Sheridan, Legislative Guide for Drafting Family and Juvenile Court Acts § 20(a)(1) (Dept, of HEW, Children’s Bureau, Pub. No. 472-1969); see also Standards for Juvenile and Family Courts 62-63 (Dept, of HEW, Children’s Bureau, *268Pub. No. 437-1966). Cf. Institute of Judicial Administration/American Bar Association Project on Juvenile Justice Standards Relating to Interim Status: The Release, Control, and Detention of Accused Juvenile Offenders Between Arrest and Disposition § 3.2(B) (Tent. Draft 1977) (detention limited to “reducing the likelihood that the juvenile may inflict serious bodily harm on others during the interim”).
Appellees argue that some limit must be placed on the categories of crimes that detained juveniles must be accused of having committed or being likely to commit. But the discretion to delimit the categories of *269crimes justifying detention, like the discretion to define criminal offenses and prescribe punishments, resides wholly with the state legislatures. Whalen v. United States, 445 U. S. 684, 689 (1980); Rochin v. California, 342 U. S. 165, 168 (1952). See also Rummel v. Estelle, 445 U. S. 263, 275 (1980) (“the presence or absence of violence does not always affect the strength of society’s interest in deterring a particular crime”).
More fundamentally, this sort of attack on a criminal statute must be made on a case-by-ease basis. United States v. Raines, 362 U. S. 17, 21 (1960). The Court will not sift through the entire class to determine whether the statute was constitutionally applied in each ease. And, outside the limited First Amendment context, a criminal statute may not be attacked as overbroad. See New York v. Ferber, 458 U. S. 747 (1982).
For good cause shown, the court may adjourn the hearing, but for no more than three additional court days. FCA § 325.1(3).
In either case, the court may adjourn the hearing for not more than three days for good cause shown. FCA §340.1(3). The court must state on the record the reason for any adjournment. § 340.1(4).
For example, as the Court of Appeals itself admits, 689 P. 2d, at 369, n. 18, the statistical study on which it relied mingles indiscriminately detentions under §320.5(3)(b) with detentions under § 320.5(3)(a). The latter provision applies only to juveniles who are likely not to appear on the return date if not detained, and appellees concede that such juveniles may be lawfully detained. Brief for Appellees 93. Furthermore, the 34 case histories on which the court relied were handpicked by appellees’ counsel from over a 3-year period. Compare Petitioners’ Exhibit 19a (detention of Geraldo Delgado on March 5,1976) with Petitioners’ Exhibit 35a (detention of James Ancrum on August 19, 1979). The Court of Appeals stated that appellants did not contest the representativeness of these case histories. 689 F. 2d, at 369, n. 19. Appellants argue, however,'that there was no occasion to contest their representativeness because the case histories were not even offered by appellees as a representative sample, and were not evaluated by appellees’ expert statistician or the District Court in that light. See Brief for Appellant in No. 82-1278, pp. 24-25, n.**. We need not resolve this controversy.
Judge Quinones testified that detention at disposition is considered a “harsh solution.” At the dispositional hearing, the Family Court judge usually has “a much more complete picture of the youngster” and tries to tailor the least restrictive dispositional order compatible with that picture. Testimony of Judge Quinones, App. 279-281.
Several amici argue that similar statistics obtain throughout the country. See, e. g., Brief for American Bar Association as Amicus Curiae 23; Brief for Association for Children of New Jersey as Amicus Curiae 8, 11; Brief for Youth Law Center et al. as Amici Curiae 13-14. But even if New York’s experience were duplicated on a national scale, that fact would not lead us, as amici urge, to conclude that every State and the United States are illicitly punishing juveniles prior to their trial. On the contrary, if such statistics obtain nationwide, our conclusion is strengthened that the existence of the statistics in these cases is not a sufficient ground for striking down New York’s statute. As already noted: “The fact that a practice is followed by a large number of states is not conclusive in a decision as to whether that practice accords with due process, but it is plainly worth considering in determining whether the practice ‘offends some principle of justice so rooted in the traditions and conscience of our people as to be ranked as fundamental’ Snyder v. Massachusetts, 291 U. S. 97, 105 (1934).” Leland v. Oregon, 343 U. S. 790, 798 (1952).
Appellees urge the alleged lack of procedural safeguards as an alternative ground for upholding the judgment of the Court of Appeals. Brief for Appellees 62-75. The court itself intimated that it would reach the same result on that ground, 689 P. 2d, at 373-374, and Judge Newman, in his concurrence, relied expressly on perceived procedural flaws in the statute. Accordingly, we deem it necessary to consider the question.
If the juvenile’s parent or guardian fails to appear after reasonable and substantial efforts have been made to notify such person, the court must appoint a law guardian for the child. FCA § 320.3.
If the child chooses to remain silent, he is assumed to deny the charges. FCA §321.1. With the consent of the court and of the presentment agency, the child may admit to a lesser charge. If he wishes to admit to the charges or to a lesser charge, the court must, before accepting the admission, advise the child of his right to a factfinding hearing and of the possible specific dispositional orders that may result from the admission. Ibid. The court must also satisfy itself that the child actually did commit the acts to which he admits. Ibid.
With the consent of the victim or complainant and the juvenile, the court may also refer a case to the probation service for adjustment. If the case is subsequently adjusted, the petition is then dismissed. § 320.6.
Given that under Gerstein, 420 U. S., at 119-123, a probable-cause hearing may be informal and nonadversarial, a Family Court judge could make a finding of probable cause at the initial appearance. That he is not required to do so does not, under the circumstances, amount to a deprivation of due process. Appellees fail to point to a single example where probable cause was not found after a decision was made to detain the child.
The Court in Gerstein indicated approval of pretrial detention procedures that supplied a probable-cause hearing within five days of the initial detention. Id,., at 124, n. 25. The brief delay in the probable-cause hearing may actually work to the advantage of the juvenile since it gives his counsel, usually appointed at the initial appearance pursuant to FCA § 320.2(2), time to prepare.
statutory improvements. These suggested changes included: limitations on the crimes for which the juvenile has been arrested or which he is likely to commit if released; a determination of the likelihood that the juvenile committed the crime; an assessment of the juvenile’s background; and a more specific standard of proof. The first and second of these suggestions have already been considered. See nn. 18 and 27, supra. We need only add to *278the discussion in n. 18 that there is no indication that delimiting the category of crimes justifying detention would improve the accuracy of the § 320.5(3)(b) determination in any respect. The third and fourth suggestions are discussed in text, infra.
See Jurek v. Texas, 428 U. S. 262, 274-275 (1976) (death sentence imposed by jury); Greenholtz v. Nebraska Penal Inmates, 442 U. S. 1, 9-10 (1979) (grant of parole); Morrissey v. Brewer, 408 U. S. 471, 480 (1972) (parole revocation).
A prediction of future criminal conduct may also form the basis for an increased sentence under the “dangerous special offender” statute, 18 U. S. C. § 3575. Under § 3575(f), a “dangerous” offender is defined as an individual for whom “a period of confinement longer than that provided for such [underlying] felony is required for the protection of the public from further criminal conduct by the defendant.” The statute has been challenged numerous times on the grounds that the standard is unconstitutionally vague. Every Court of Appeals considering the question has rejected that claim. United States v. Davis, 710 F. 2d 104, 108-109 (CA3), cert. denied, 464 U. S. 1001 (1983); United States v. Schell, 692 F. 2d 672, *279675-676 (CA10 1982); United States v. Williamson, 567 F. 2d 610, 613 (CA4 1977); United States v. Bowdach, 561 F. 2d 1160, 1175 (CA5 1977); United States v. Neary, 552 F. 2d 1184,1194 (CA7), cert. denied, 434 U. S. 864 (1977); United States v. Stewart, 531 F. 2d 326, 336-337 (CA6), cert. denied, 426 U. S. 922 (1976).