(concurring). I concur with the court’s answers to the reported questions. However, I depart from the court’s reasoning.
The Juvenile Court judge has asked generally if Lowell’s curfew ordinance is unconstitutional and specifically whether it violates equal protection. He also asks what is the appropriate standard of review. The court notes that under both the Massachusetts and the United States Constitutions, “[wjhere a statute implicates a fundamental right or uses a suspect classification, we employ ‘strict judicial scrutiny.’ ” Ante at 30, quoting Goodridge v. Department of Pub. Health, 440 Mass. 309, 330 (2003). As the court acknowledges, because age is not a suspect classification, Gregory v. Ashcroft, 501 U.S. 452, 470 (1991), there is no equal protection violation merely because the curfew rules apply only to juveniles. The court continues its equal protection analysis by inquiring whether the ordinance implicates a funda*42mental right guaranteed by either Constitution. It is in this context that the court, for the first time, holds that the Massachusetts Constitution includes a fundamental right to “free movement.” Ante at 32-33. I do not think it is necessary to articulate a new right to decide this case. The court can reach the same conclusions by relying on our precedents defining a fundamental right to liberty.
While the equal protection approach has merit, an equally appropriate (and in my view a preferred) analysis is to determine whether the ordinance violates substantive due process. Substantive due process “prevents the government from engaging in conduct that ‘shocks the conscience,’ ... or interferes with rights ‘implicit in the concepts of ordered liberty.’ ” Commonwealth v. Bruno, 432 Mass. 489, 503 (2000), quoting Aime v. Commonwealth, 414 Mass. 667, 673 (1993). When considering the right to liberty, we have most often done so in the context of due process, not equal protection. Most recently, we reiterated that “[f]reedom from bodily restraint is a fundamental liberty interest at the core of the protections provided under the due process clause of the Fourteenth Amendment to the Federal Constitution.” Kenniston v. Department of Youth Servs., 453 Mass. 179, 183 (2009), and cases cited.
In analyzing whether a fundamental right is implicated, the court first should turn to our precedents. Liberty is a fundamental right. A curfew by definition, or at least by strong implication, is a deprivation of liberty as it confines those individuals subject to it to the indoors. The Lowell ordinance requires the juvenile to remain in his home for six hours each day under threat of prosecution. This is a substantial infringement on liberty. As the court notes, “a minor who violates the criminal provisions of a municipal ordinance may be adjudicated to be a ‘delinquent child’ . . . [and] [o]nce a child is deemed ‘delinquent,’ Juvenile Court judges have the authority to commit the minor to the custody of the [Department of Youth Services (DYS)] until age eighteen.” Ante at 39. Because of the liberty lost by the imposition of the curfew and the threat of institutionalization after commitment to DYS, a strict scrutiny analysis is appropriate.
Although the loss of liberty experienced under the Lowell curfew is not incarceration, it is a form of house arrest that is so *43intrusive on liberty as to warrant analogy to that precedent. For example, the United States Supreme Court has “repeatedly . . . recognized that civil commitment for any purpose constitutes a significant deprivation of liberty that requires due process protection.” Addington v. Texas, 441 U.S. 418, 425 (1979). See Guardianship of Roe, 383 Mass. 415, 424 (1981) (“confinement for any purpose constitutes a significant deprivation of liberty” requiring due process [beyond a reasonable doubt standard]). See also Commonwealth v. Nassar, 380 Mass. 908, 917 (1980), quoting Lessard v. Schmidt, 349 F. Supp. 1078, 1093 (E.D. Wis. 1972), vacated and remanded on other grounds, 414 U.S. 473 (1974) (commitment of mentally ill “massive curtailment of liberty” implicating due process [enhanced standard of proof]). Further, in Newton-Wellesley Hosp. v. Magrini, 451 Mass. 777, 784 (2008), citing Commonwealth v. Nassar, supra, we recognized that even “temporary involuntary commitment” is a “massive curtailment” of liberty. Here, the court recognizes that “[w]hen imposed carelessly, curfews constitute a potentially devastating restriction on fundamental rights.” Ante at 34 n.14, citing Power, Pinochet and the Uncertain Globalization of Criminal Law, 39 Geo. Wash. Int’l L. Rev. 89, 97 (2007). Cf. Commonwealth v. Nassar, supra at 916-917 (civil commitment under G. L. c. 123 need not involve commitment to State institution with total loss of liberty).
Where the fundamental right at stake is liberty, the substantive due process analysis undertaken by this court in Paquette v. Commonwealth, 440 Mass. 121, 124-125 (2003), cert. denied, 540 U.S. 1150 (2004) (pretrial detention after bail revocation), and Commonwealth v. Bruno, 432 Mass. 489 (2000) (commitment of allegedly sexual dangerous persons), is comparable to the equal protection analysis the court employs in this case. In those cases we explained that where the right involved “is ‘fundamental,’ we ‘ “must examine carefully the importance of the governmental interests advanced and the extent to which they are served by the challenged regulation.” Moore v. East Cleveland, 431 U.S. 494, 499 (1977).’ Aime v. Commonwealth, 414 Mass. 667, 673 (1993). See Commonwealth v. Bruno, 432 Mass. 489, 503 (2000). A State ‘may impose a regulatory restraint on the individual in narrowly-circumscribed situations.’ A statute *44imposing such a restraint typically will be upheld only if it is ‘narrowly tailored to further a legitimate and compelling governmental interest.’ Id. at 673.” Paquette v. Commonwealth, supra at 125. See Commonwealth v. Bruno, supra.
Applying a substantive due process analysis based to the loss of liberty, I would hold that the ordinance’s civil penalties “represent ... a permissible, narrowly tailored response to Lowell’s compelling interest in preventing crime by, and against, minors.” Ante at 41. Furthermore, “[t]he right to substantive due process under the United States Constitution protects individuals from unreasonable governmental interference with fundamental rights.” Kenniston v. Department of Youth Servs., supra at 183, and cases cited. Therefore, the criminal penalties resulting from violations of the curfew ordinance violate the fundamental right of liberty possessed by minors within the Commonwealth, under the Massachusetts Declaration of Rights. I see no need to create a new fundamental right to decide this case, and would decide this case on principles of due process.