SPINA, J.

In this case, here on a reservation and report by a single justice of this court, we consider whether the Massachusetts firearms licensing statute, G. L. c. 140, § 131 (d) (i), infringes on Mirko Chardin's right to keep and bear arms under the Second and Fourteenth Amendments to the United States Constitution because it precludes him from ever obtaining a license to carry firearms where, in 1995, he was adjudicated a delinquent child2 after admitting to sufficient facts on a complaint charging him with one count of possession of a firearm without a license, and one count of unlawful possession of ammunition. We conclude that, consistent with the United States Supreme Court's decisions in District of Columbia v. Heller, 554 U.S. 570 (2008) (Heller), and McDonald v. Chicago, 130 S.Ct. 3020 (2010) (McDonald), the challenged statute does not infringe on a right protected by the Second Amendment.3

1. Statutory scheme. An individual who lawfully wants to carry a firearm4 within the Commonwealth either must obtain a license to do so pursuant to G. L. c. 140, § 131, or be exempt from the statutory licensing requirements.5 See, e.g., G. L. c. 140, §§ 129C, 131F, 131G. See also Commonwealth v. Seay, 376 Mass. 735, 739 (1978). "The historical aim of licensure generally is preservation of public health, safety, and welfare by extending the public trust only to those with proven qualifications." Leduc v. Commonwealth, 421 Mass. 433, 435 (1995), cert. denied, 519 U.S. 827 (1996). In Massachusetts, there are two categories of licenses to carry firearms — Class A and Class B. See G. L. c. 140, § 131 (a) & (b). Each type of license may be issued by a "licensing authority," defined as "the chief of police or the board or officer having control of the police in a city or town, or persons authorized by them," G. L. c. 140, § 121, or by the colonel of the State police, G. L. c. 140, § 131 (d). The Class A license, which is the focus of this case, authorizes the holder to possess and carry "firearms, including large capacity firearms, and feeding devices and ammunition therefor, for all lawful purposes, subject to such restrictions relative to the possession, use or carrying of firearms as the licensing authority deems proper."6 G. L. c. 140, § 131 (a). In the absence of a restriction, G. L. c. 140, § 131 (a), does not prohibit the possession or carrying of a concealed firearm in public. See Hightower v. Boston, 693 F.3d 61, 66 (1st Cir.2012). Contrast G. L. c. 140, § 131 (b) (precluding holder of Class B license from possessing or carrying loaded firearm "in a concealed manner in any public way or place").

The licensing authority or colonel of the State police may issue a Class A license to carry firearms "if it appears that the applicant is a suitable person to be issued such license, and that the applicant has good reason to fear injury to his person or property, or for any other reason." G. L. c. 140, § 131 (d). The "suitable person" standard gives the licensing authority or colonel "considerable latitude" or broad discretion in making a licensing decision. Ruggiero v. Police Comm'r of Boston, 18 Mass.App.Ct. 256, 259 (1984). See Howard v. Chief of Police of Wakefield, 59 Mass.App.Ct. 901, 902 (2003). However, an applicant is statutorily disqualified from obtaining a license to carry firearms if, among other reasons, the applicant "has, in any state or federal jurisdiction, been convicted or adjudicated a youthful offender or delinquent child for the commission of (a) a felony...."7 G. L. c. 140, § 131 (d) (i).

Within forty days from the date of the application, the licensing authority shall "either approve the application and issue the license or deny the application and notify the applicant of the reason for such denial in writing." G. L. c. 140, § 131 (e). If an application is denied, the aggrieved party may file, within ninety days after receiving notice, "a petition to obtain judicial review in the district court having jurisdiction in the city or town" where the application was filed. G. L. c. 140, § 131 (f). A judge, after an evidentiary hearing, may direct that a license be issued to the petitioner if the judge finds that there was "no reasonable ground" for denying such license, and that the petitioner "is not prohibited by law from possessing [the] same." Id. See Godfrey v. Chief of Police of Wellesley, 35 Mass.App.Ct. 42, 44-45 (1993). The petitioner is entitled to relief only if the licensing authority's denial was "arbitrary, capricious, or an abuse of discretion." Id. at 46, quoting Chief of Police of Shelburne v. Moyer, 16 Mass.App.Ct. 543, 546 (1983). Further judicial review is available to the petitioner by way of an action in the nature of certiorari. See G. L. c. 249, § 4. See also Levine v. Chief Justice of the Dist. Court Dep't of the Trial Court, 434 Mass. 1014, 1014 (2001); Godfrey v. Chief of Police of Wellesley, supra.

2. Factual and procedural history. The essential facts are not disputed. In early 1995, when Chardin was fourteen years old, one of his best friends was shot and killed for the pair of sneakers that the friend had been wearing. Fearing for his personal safety, Chardin obtained a handgun for his own protection. He never used it to commit a crime or threaten anyone. On January 18, 1995, while Chardin was standing in front of a plain-clothed police officer, the handgun fell from the pocket of his pants onto the ground. Chardin was arrested and taken into custody.

On January 19, 1995, he was charged in the Juvenile Court with one count of possession of a firearm without a license, and one count of unlawful possession of ammunition.8 On April 18, 1995, Chardin admitted to sufficient facts and was adjudicated a delinquent child with respect to both charges. He received a suspended commitment to the Department of Youth Services, was released to his mother's custody, and was given probation until April 18, 1996.

In the years since this incident, Chardin has been a law-abiding citizen. He graduated from college, earned a master's degree in teaching, has been working toward a Ph.D. in education, became an ordained minister, and has done volunteer work in his community. Chardin currently is employed as the head of the Putnam Avenue Upper School in Cambridge. He also is a coowner and manager of a small used car dealership in the Roslindale area of Boston, JBI Auto Sales LLC (JBI). He works there part-time, at night and on the weekends, and he regularly attends car auctions to buy vehicles for JBI. At these auctions, purchases must be made in cash, so Chardin is required to carry large amounts of money on his person, which has caused him to fear for his safety. In addition, JBI has a night deposit agreement with Citizens Bank whereby Chardin regularly makes large cash deposits for JBI, again raising personal safety concerns.

On April 26, 2010, Chardin submitted to the Boston police department an application for an unrestricted Class A license to carry firearms, which he stated that he was requesting for "all lawful purpose[s]," together with a fee of $100.9 On an attached worksheet, Chardin responded more specifically to a question about why he required such a license by stating that it was for "club use"10 and for "protection as a used car dealer who is required to make large cash purchases/transactions." By letter dated July 26, 2010, the police commissioner, who is the licensing authority for the city of Boston under G. L. c. 140, §§ 121 and 131, denied the application, stating: "[Y]ou have a sealed record with a disqualifying conviction(s) as outlined in chapter 180 of the Acts of 1998."

On October 15, 2010, Chardin filed a complaint for judicial review in the Boston Municipal Court pursuant to G. L. c. 140, § 131(f).11 He stated that he was seeking a Class A license to carry firearms "due to the dangers involved in his used car dealership business." In Count I of his complaint, Chardin alleged that the denial of his application was based on an error of law in that he did not have any convictions or adjudications on his juvenile record that would disqualify him under G. L. c. 140, § 131 (d) (i), from obtaining a license because the charges on his record ultimately were dismissed. In Count II, Chardin alleged that the denial of his application was a mistake due to the absence of disqualifying factors. Finally, in Count III of his complaint, Chardin alleged that if his juvenile charges were deemed to be automatic disqualifiers under G. L. c. 140, § 131 (d) (i), then the statute, as applied to Chardin, was unconstitutional because it violated his fundamental right to keep and bear arms as guaranteed by the Second and Fourteenth Amendments to the United States Constitution pursuant to Heller, 554 U.S. at 635, and McDonald, 130 S.Ct. at 3050.12

An evidentiary hearing was held on March 15, 2011. Although the judge agreed with the police commissioner that the only issue before her was the applicability of G. L. c. 140, § 131 (d) (i), to Chardin's circumstances, she allowed Chardin to testify regarding his suitability for a license.13 Chardin described the events leading up to his adjudication as a delinquent child, and the path his life had taken since that time. Among other things, he stated that he only would use a firearm in circumstances where he or a family member was in danger, and he responded "[y]es" when his attorney asked whether that would include "at the auctions or at home." Testimony also was presented from Lieutenant Mark Harrington of the Boston police department who, on behalf of the police commissioner, had reviewed Chardin's application. He stated that once he received notice of Chardin's statutory disqualification, due to his adjudication as a delinquent child for possession of a firearm without a license, he did not go any further in the application process. On March 30, 2011, the judge found that Chardin was "statutorily disqualified from possessing a license to carry a firearm."14 The following day, the judge entered a judgment of dismissal in favor of the police commissioner.

On April 8, 2011, Chardin filed a notice of appeal in the Boston Municipal Court. Six months later, he filed an action in the nature of certiorari, pursuant to G. L. c. 249, § 4, in the Supreme Judicial Court for Suffolk County. He alleged that G. L. c. 140, § 131 (d) (i), as applied to his circumstances, violated his right to keep and bear arms under the Second and Fourteenth Amendments to the United States Constitution. The Attorney General, on behalf of the Commonwealth, was allowed to intervene to defend the constitutionality of the statute. On April 6, 2012, the single justice reserved and reported the case for decision by the full court.15

3. Constitutional framework. The Second Amendment to the United States Constitution provides: "A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed." To determine whether G. L. c. 140, § 131 (d) (i), impermissibly burdens Chardin's Second Amendment right, we begin with Heller. In that case, the United States Supreme Court considered whether "a District of Columbia prohibition on the possession of usable handguns in the home" violated the Second Amendment. Heller, supra at 573. Based on textual and historical analyses, the Court concluded that the Second Amendment guarantees an individual right to keep and bear firearms in one's home for the purpose of self-defense.16 See id. at 635. The Court opined that the Second Amendment "surely elevates above all other interests the right of law-abiding, responsible citizens to use arms in defense of hearth and home."17 Id. Since Heller, "[c]ourts have consistently recognized that Heller established that the possession of operative firearms for use in defense of the home constitutes the `core' of the Second Amendment." Hightower v. Boston, 693 F.3d 61, 72 (1st Cir. 2012), citing United States v. Booker, 644 F.3d 12, 25 n.17 (1st Cir.2011), cert. denied, 132 S.Ct. 1538 (2012). See Commonwealth v. McGowan, 464 Mass. 232, 235 (2013) (McGowan), and cases cited. Two years after its decision in Heller, a plurality of the Supreme Court held in McDonald, supra, that an individual's Second Amendment right was fully applicable to the States through the Fourteenth Amendment to the United States Constitution.

Notwithstanding its articulation in Heller of an individual right to keep and bear arms in one's home for self-defense, the Supreme Court also recognized that the Second Amendment right is "not unlimited, just as the First Amendment's right of free speech ... [does not] protect the right of citizens to speak for any purpose" (emphasis in original). Heller, supra at 595. It pointed out that "[f]rom Blackstone through the 19th-century cases, commentators and courts routinely explained that the right was not a right to keep and carry any weapon whatsoever in any manner whatsoever and for whatever purpose." Id. at 626. As such, the Court continued, an individual's Second Amendment right does not prohibit laws regulating who may purchase, possess, and carry firearms, and where such weapons may be carried. See id. at 626-627. Although the Supreme Court did not undertake "an exhaustive historical analysis" of the full scope of the Second Amendment, it identified an expressly nonexclusive list of "presumptively lawful regulatory measures," declaring that nothing in Heller "should be taken to cast doubt on longstanding prohibitions on the possession of firearms by felons and the mentally ill, or laws forbidding the carrying of firearms in sensitive places such as schools and government buildings, or laws imposing conditions and qualifications on the commercial sale of arms."18 Id. at 626-627 & n.26. Notably, the Court reiterated in McDonald its recognition of these permissible limitations when it stated that the Fourteenth Amendment's incorporation of Second Amendment rights "does not imperil every law regulating firearms." McDonald, supra at 3047.

With regard to the regulation of firearms, the Supreme Court made clear in Heller that "a law that infringes the right to bear arms in self-defense within the scope of the Second Amendment is subject to some level of heightened scrutiny, rejecting the notion that rational basis scrutiny would suffice." McGowan, supra at 237. See Heller, supra at 628 n.27. However, the Court declined to "identify precisely what level of heightened scrutiny is appropriate because it concluded that the District of Columbia's outright ban on handguns would fail under any level of scrutiny." McGowan, supra at 237-238. See Heller, supra at 628-629. Nonetheless, we have "discern[ed] meaning from the Supreme Court's willingness to characterize some long-standing limitations on the right to bear arms, such as the prohibition of the possession of firearms by felons and the mentally ill, ... as `presumptively lawful' without subjecting these laws to heightened scrutiny, or identifying the level of heightened scrutiny that would apply. These laws could be presumptively lawful without such heightened scrutiny only if they fell outside the scope of the Second Amendment and therefore were not subject to heightened scrutiny."19 McGowan, supra at 238, quoting Heller, supra at 627 n.26. See United States v. Marzzarella, 614 F.3d 85, 91 (3d Cir.2010), cert. denied, 131 S.Ct. 958 (2011) ("presumptively lawful" language in Heller intended to put certain recognized prohibitions outside ambit of Second Amendment right delineated in Heller). In other words, long-standing and "presumptively lawful" regulations on the right to keep and bear arms "do not burden conduct that falls within the scope of the Second Amendment and therefore are not subject to the heightened scrutiny required where protected conduct within the scope of the Second Amendment is infringed."20 McGowan, supra at 239. See, e.g., United States v. Booker, supra at 23-24 (felony firearm disqualification is presumptively lawful and only burdens conduct outside scope of Second Amendment); United States v. Marzzarella, supra (long-standing firearms prohibitions, such as possession by felons and mentally ill persons, are exceptions to right to bear arms); United States v. Rene E., 583 F.3d 8, 15-16 (1st Cir. 2009), cert. denied, 130 S.Ct. 1109 (2010) (Federal statute barring juveniles from possessing handguns, with limited exceptions, consistent with long-standing practice of prohibiting certain classes of individuals from possessing firearms and not offensive to Second Amendment right). Contrast United States v. Chester, 628 F.3d 673, 681, 683 (4th Cir.2010) (intermediate scrutiny of Federal firearms prohibition appropriate because court "not able to say that the Second Amendment, as historically understood, did not apply to persons convicted of domestic violence misdemeanors").

4. Discussion. In 1995, when Chardin was adjudicated a delinquent child for possession of a firearm without a license, see note 8, supra, G. L. c. 269, § 10 (a), provided that such an offense was punishable by "imprisonment in the state prison for not less than two and one-half years nor more than five years, or for not less than one year nor more than two and one-half years in a jail or house of correction." St.1990, c. 511, § 2. A crime punishable by imprisonment in the State prison is a felony. See G. L. c. 274, § 1. Therefore, possession of a firearm without a license was (and still is) a felony in Massachusetts.21 See Yanovitch v. United States, 985 F.Supp. 17, 21 (D.Mass.1997). That Chardin could not be sentenced to the State prison, see Commonwealth v. Connor C., 432 Mass. 635, 641 (2000), does not change the nature of his offense, even though an "adjudication" of delinquency generally is not a "conviction" of a crime. Id. at 646 (expressly adhering to long-standing jurisprudence governing delinquent children, notwithstanding narrow holding that adjudication of delinquency for possession of firearm without license constitutes prior "conviction" under second offense penalty provision of G. L. c. 269, § 10 [d]). See Department of Youth Servs. v. A Juvenile, 384 Mass. 784, 786 (1981). In other words, although the juvenile justice system did not treat Chardin as a "criminal" for his possession of a firearm without a license, as evidenced by the disposition of the charges against him, he nonetheless committed an unlawful act that was a felony. See Stokes v. Commonwealth, 368 Mass. 754, 772 (1975) (act committed by juvenile against laws of Commonwealth is criminal act).

It has been a "long-standing principle" in Massachusetts that "the treatment of children who offend our laws are not criminal proceedings." Commonwealth v. Connor C., supra at 641. See Commonwealth v. Anderson, 461 Mass. 616, 629-630, cert. denied, 133 S.Ct. 433 (2012); Department of Youth Servs. v. A Juvenile, supra. General Laws c. 119, § 53, sets forth a legislative policy that statutory provisions dealing with delinquent children shall be construed liberally such that children brought before court, "as far as practicable, ... shall be treated, not as criminals, but as children in need of aid, encouragement and guidance."22 See Commonwealth v. Magnus M., 461 Mass. 459, 461, 466 (2012) (discussing underlying philosophy and goals of juvenile justice system); R.L. Ireland, Juvenile Law § 1.3, at 18-32 (2d ed.2006) (same). This statutory provision has remained unchanged since the chapter's original enactment in 1906, see St.1906, c. 413, § 2, entitled "An Act relative to delinquent children." Significantly, G. L. c. 119, § 53, was firmly in place when the Legislature enacted G. L. c. 140, § 131 (d) (i). See St.1998, c. 180, § 41. Given that the "Legislature is presumed to be aware of existing statutes when it ... enacts a new one," Paquette v. Commonwealth, 440 Mass. 121, 130 (2003), cert. denied, 540 U.S. 1150 (2004), we conclude that the Legislature intended to preclude an individual who has been adjudicated a delinquent child for the commission of a felony from obtaining a license to carry firearms, notwithstanding the policy enunciated in G. L. c. 119, § 53. If the Legislature had wanted to exclude this class of persons from the provisions of G. L. c. 140, § 131 (d) (i), it would not have expressly disqualified such persons from licensure.

Given that the Legislature has determined, as is its purview, that an adjudication as a delinquent child for the commission of a felony is a categorical bar to obtaining a license to carry firearms, the question becomes whether G. L. c. 140, § 131 (d) (i), infringes on Chardin's Second Amendment right to keep and bear arms as articulated in Heller, supra at 635, and McDonald, supra at 3050. In conformity with our discussion of the constitutional framework of this case, we conclude that § 131 (d) (i) does not burden conduct that falls within the scope of the Second Amendment. To the contrary, the statute embodies a long-standing and well-recognized prohibition on the possession of firearms by a particular group of individuals — those who have committed a felony — and is clearly encompassed within the "presumptively lawful regulatory measures" that Heller has declared to be outside the ambit of the Second Amendment. See Heller, supra at 626-627 & n.26. Accordingly, we conclude that G. L. c. 140, § 131 (d) (i), passes constitutional muster. Chardin's challenge to the statute is unavailing, and the Commonwealth may continue to enforce its provisions to protect the health, safety, and welfare of its citizens.

Our interpretation of G. L. c. 140, § 131 (d) (i), does not run afoul of recent Supreme Court jurisprudence recognizing the reduced culpability of juveniles as compared to adults and declaring unconstitutional the imposition of the harshest criminal penalties on juvenile offenders. First, in Roper v. Simmons, 543 U.S. 551, 564, 569-570, 578-579 (2005), the Court held that, in light of a "national consensus against the death penalty for juveniles" and the general immaturity and vulnerability of those under eighteen years of age, imposition of the death penalty on offenders who were under that age when they committed their crimes is contrary to the prohibition on cruel and unusual punishment in the Eighth Amendment to the United States Constitution. Next, in Graham v. Florida, 130 S.Ct. 2011, 2030 (2010), the Court held that the Eighth Amendment prohibits the imposition of a sentence of life in prison without the possibility of parole on a juvenile offender who does not commit the crime of homicide. The Court stated that such a "categorical rule gives all juvenile nonhomicide offenders a chance to demonstrate maturity and reform." Id. at 2032. Most recently, in Miller v. Alabama, 132 S.Ct. 2455, 2469 (2012), the Court concluded that sentencing a juvenile to mandatory life imprisonment without the possibility of parole (as required for a conviction of murder in the first degree) similarly violates the Eighth Amendment prohibition on cruel and unusual punishment. That decision reaffirmed the "diminished culpability and greater prospects for reform" of juvenile offenders. Id. at 2464.

These cases highlighted the draconian consequences flowing from the imposition of the most severe criminal penalties on juvenile offenders who, because of their age and immaturity, are deemed to have lesser culpability than their adult counterparts. As the Supreme Court stated in Miller v. Alabama, supra at 2463, quoting Roper v. Simmons, supra at 560, "[t]he Eighth Amendment's prohibition of cruel and unusual punishment `guarantees individuals the right not to be subjected to excessive sanctions'.... That right ... `flows from the basic "precept of justice that punishment for crime should be graduated and proportioned"' to both the offender and the offense." The Court's Eighth Amendment jurisprudence "make[s] clear that the prohibition against cruel and unusual punishment applies only to punishments. It does not apply to equally burdensome regulatory measures that may be characterized as cruel and even unusual." Opinion of the Justices, 423 Mass. 1201, 1238 (1996). It is axiomatic that G. L. c. 140, § 131, is a regulatory statute, and that its prohibition on the issuance of a license to carry firearms to an individual who has been adjudicated a delinquent child for the commission of a felony is not a criminal penalty. See Dupont v. Chief of Police of Pepperell, 57 Mass.App.Ct. 690, 694 (2003) ("statute governing who may carry firearms is not punitive"). Therefore, the Eighth Amendment prohibition against cruel and unusual punishment is not applicable to Chardin's circumstances.23

5. Conclusion. General Laws c. 140, § 131 (d) (i), does not infringe on Chardin's right to keep and bear arms under the Second and Fourteenth Amendments to the United States Constitution. Accordingly, this case is remanded to the county court where the single justice shall enter a judgment denying the petition.

So ordered.