Streeter, J.

Certified for Partial Publication.

Counsel for Defendant and Appellant: Leila H. Moncharsh, by appointment of the Court of Appeal under the First District Appellate Project's Assisted–Case System.

Counsel for Plaintiff and Respondent: Kamala D. Harris, Attorney General of California, Gerald A. Engler, Senior Assistant Attorney General, Eric D. Share, Supervising Deputy Attorney General, Sharon G. Birenbaum, Deputy Attorney General.

Streeter, J. After determining that defendant Kevin F. (Minor) committed robbery, the juvenile court declared Minor a ward of the court and placed him on probation with conditions. On appeal, Minor contends (1) there is insufficient evidence he committed robbery, and (2) the court's probation condition prohibiting him from possessing weapons is unconstitutionally vague and overbroad. In the unpublished portion of this opinion, we reject Minor's challenge to the sufficiency of the evidence. In the published portion of this opinion, we hold the challenged probation condition must be modified. We will affirm the judgment as modified.

I. BACKGROUND

A. The Robbery

On October 17, 2013, about 11:00 p.m., Samuel Merlo boarded the J–Church Muni train at Church and Market Streets in San Francisco. He sat down and took out his cell phone. Merlo noticed a group of three or four young men sitting near him talking to each other. At the jurisdictional hearing, Merlo identified Minor as one of the people in this group. Minor was wearing a white shirt and a baseball cap. Merlo stated the group also included a Latino male, an African–American male, and perhaps another person. At the jurisdictional hearing, Merlo identified a photograph of a Latino male with a long ponytail as one of the people in the group.

Minor and the other members of the group began talking with Merlo. Merlo told them his name was Sam, and Minor said his name was "Kev." They spoke for 10 to 15 minutes. Minor gave Merlo his phone number, which Merlo put in his phone. Merlo was a social person and relatively new to San Francisco, and he thought Minor and his friends seemed nice. Merlo and the others got off the train at the same station. Merlo went into a liquor store, where he bought a pack of cigarettes. The African–American male went into the store with Merlo. After leaving the store, they rejoined the rest of the group, including Minor, who had waited a bit further down the sidewalk.

Merlo felt comfortable with Minor and the other men in the group. They walked together in the direction of Merlo's house. As they were walking and talking, the street "suddenly an[d] inconspicuously turn[ed] into an alley." The alley was dark. Merlo stated, "[The alley was] somewhat paved, somewhat not.... It turned from a normal residential street with a nice sidewalk to an alley that's unkempt." The young men were laughing and talking. Merlo stated, "there was no intensity," and "there was no shift or there was no sign to me that something was about to happen."

Merlo was walking to the right of the others, and the man with the ponytail was closest to him. Minor was still with the group. When they were in the alley, the man with the ponytail suddenly got behind Merlo, "quickly reached around with his left arm, grabbed [Merlo] by the neck, and yelled, get him." The other young men rushed Merlo and pushed him so he was bent forward at the waist and facing the ground, although he remained on his feet. Merlo believed everyone in the group pushed him. He "was pushed by everyone forward, and then bent forward, they all came on top of me, and then I was punched from several directions." The young men punched Merlo more than four times (all in the head), including punching his left eye and his jaw. Merlo could not identify any individual as doing a particular act, but he believed each man was participating in the assault because he was "being punched in different directions." Merlo did not see any of the men not punching him. He did not hear anyone in the group tell the others to stop.

The attackers took everything out of Merlo's pants pockets. As they did so, they described the items, including his wallet, cell phone and keys. Merlo begged them to return the keys. The man with the ponytail asked Merlo what kind of car he drove. Merlo said it was "just a piece of shit." Someone eventually put the keys back in Merlo's pocket. No one returned Merlo's wallet or phone. Merlo heard all of the men speaking, but was unsure as to who said what. Merlo recalled the man with the ponytail put him in a chokehold, said to "get him," and asked Merlo about his keys and what kind of car he drove. Other than that, Merlo could not specify what each participant said.

The man holding Merlo's neck let go. The group ran down the alley, and Merlo chased them. One of the men fell on his stomach, and the man with the ponytail who had been choking Merlo, turned around, faced Merlo, and took an aggressive stance. Merlo stepped back. The person who had fallen got up, and he and the man with the ponytail started running again. Merlo continued to chase them, yelling that he was "just like [them]" and needed his phone and wallet. Merlo caught up with the men at the end of the alley. The man with the ponytail turned around again and said, "I got a knife." He pulled out a knife and flipped it open. Merlo put up his arms and stepped back. By then, the others, including Minor, had turned to the left and continued running. The man with the ponytail, after displaying the knife, ran after the others. Merlo stopped chasing them.

Police arrived. They told Merlo they were going to drive him around and show him a few people, to see if any of them looked like the people involved in the incident. Merlo told police some of the people they saw during the drive were not involved. Merlo saw and identified the Latino man who had grabbed him by the throat. Merlo also saw Minor and recognized his shirt and baseball cap. Merlo told the police, "That's Kev. That's Kev. I know him." When the police detained Minor, they did not find any weapons or any of Merlo's stolen property on him. An ambulance arrived at the scene of the incident, but Merlo refused to ride to the hospital. He did go to the hospital later. It took about two weeks for the bruises on his face to heal, and he still had a scar on his forehead at the time of the jurisdictional hearing. He suffered a black eye. Because of the punch to his jaw, it took a week before Merlo was comfortable eating.

B. Procedural Background

The San Francisco District Attorney filed a juvenile wardship petition ( Welf. & Inst. Code, § 602, subd. (a) ), alleging Minor committed second degree robbery ( Pen. Code, §§ 211, 212.5, subd. (c) ). After a contested jurisdictional hearing, the juvenile court sustained the petition. At the subsequent dispositional hearing, the court declared Minor a ward, placed him on probation on condition that he successfully complete a ranch school program, and imposed probation conditions, including a prohibition on weapons possession. Minor appealed.

II. DISCUSSION

A. Sufficiency of the Evidence

B. The Weapon Condition

1. Background

The court placed Minor on probation on condition that he successfully complete a ranch school program. At the disposition hearing, the court told Minor: "You're not to possess any weapons. You're not to possess any toys that look like weapons." The court's printed dispositional findings, which the court signed, specify probation conditions, including the requirement that Minor "[n]ot possess weapons of any kind, which means no guns, knives, clubs, brass knuckles, attack dogs, ammunition, or something that looks like a weapon. You are not to possess anything that you could use as a weapon or someone else might consider to be a weapon."

2. Analysis

Minor contends the weapon condition is unconstitutionally vague and overbroad. Under Welfare and Institutions Code section 730, subdivision (b), a juvenile court may impose "any and all reasonable conditions that it may determine fitting and proper to the end that justice may be done and the reformation and rehabilitation of the ward enhanced." In spite of the juvenile court's broad discretion, "[a] probation condition ‘must be sufficiently precise for the probationer to know what is required of him, and for the court to determine whether the condition has been violated,’ if it is to withstand a challenge on the ground of vagueness. [Citation.] A probation condition that imposes limitations on a person's constitutional rights must closely tailor those limitations to the purpose of the condition to avoid being invalidated as unconstitutionally overbroad." ( In re Sheena K. (2007) 40 Cal.4th 875, 890, 55 Cal.Rptr.3d 716, 153 P.3d 282 ( Sheena K. ).) A defendant may contend for the first time on appeal that a probation condition is unconstitutionally vague or overbroad on its face when the challenge presents a pure question of law that the appellate court can resolve without reference to the sentencing record. ( Id. at pp. 887–889, 55 Cal.Rptr.3d 716, 153 P.3d 282 ; People v. Quiroz (2011) 199 Cal.App.4th 1123, 1127, 131 Cal.Rptr.3d 925.)

The prohibition on vagueness is rooted in " ‘ordinary notions of fair play and the settled rules of law,’ and a statute that flouts it ‘violates the first essential of due process.’ " ( Johnson v. United States (2015) 576 U.S. –––, ––––, [135 S.Ct. 2551, 2557], 192 L.Ed.2d 569.) This concern for fair warning is aimed at ensuring that a " ‘person of ordinary intelligence [has] a reasonable opportunity to know what is prohibited, so that he may act accordingly.’ " ( Hoffman Estates v. Flipside, Hoffman Estates, Inc. (1982) 455 U.S. 489, 498, 102 S.Ct. 1186, 71 L.Ed.2d 362, quoting Grayned v. City of Rockford (1972) 408 U.S. 104, 108, 92 S.Ct. 2294, 33 L.Ed.2d 222.) The fear is that vague laws will " ‘trap the innocent.’ " ( 455 U.S. at p. 498, 102 S.Ct. 1186.) More broadly, " ‘ "a law that is ‘void for vagueness' ... ‘impermissibly delegates basic policy matters to policemen, judges, and juries for resolution on an ad hoc and subjective basis, with the attendant dangers of arbitrary and discriminatory application.’ " ' " ( In re H.C. (2009) 175 Cal.App.4th 1067, 1070, 96 Cal.Rptr.3d 793.)

Arguing that the juvenile court's oral statement prohibiting possession of "any weapons" or "any toys that look like weapons" does not provide an explicit standard for determining which objects are prohibited, Minor asks us to modify the condition to prohibit possession of "dangerous or deadly weapons." (Italics added.) In response, the Attorney General makes no contention that the court's oral statement, standing alone, is sufficiently precise to meet constitutional requirements, and we interpret her position as an implicit concession on this point. The Attorney General argues, however, that the more detailed written condition in the court's printed dispositional findings clarifies the prohibition by specifying which items are forbidden, i.e., "guns, knives, clubs, brass knuckles, attack dogs, ammunition," so there is no need to rewrite the condition to prohibit possession of deadly or dangerous weapons. (See Sheena K., supra, 40 Cal.4th at p. 891, 55 Cal.Rptr.3d 716, 153 P.3d 282 [a probation condition that otherwise would be deemed vague may be constitutional because the juvenile court offered additional oral or written comments clarifying the condition].) We agree the court's written condition (with modifications we discuss below) is sufficiently precise for Minor to know what is required of him.

In support of his request that we modify the condition to prohibit possession of only "dangerous or deadly" weapons, Minor relies on In re R.P. (2009) 176 Cal.App.4th 562, 97 Cal.Rptr.3d 822. In that case, the court concluded that a probation condition prohibiting a minor from possessing any " ‘dangerous or deadly weapon’ " gave sufficient warning as to the conduct that might result in a violation, and hence was not unconstitutionally vague. ( Id. at p. 565, 97 Cal.Rptr.3d 822.) The court reasoned, "[c]ase law confirms the plain meaning definition of ‘deadly weapon’ as ‘ "any object, instrument, or weapon which is used in such a manner as to be capable of producing, and likely to produce, death or great bodily injury. " [Citation.]’ [Citation.] This definition encompasses inherently deadly items such as dirks and blackjacks which are specifically designed as weapons and are thus ‘deadly weapons' as a matter of law, as well as other items that are not deadly per se but which may be used in a manner likely to cause death or great bodily injury. " ( Id. at p. 567, 97 Cal.Rptr.3d 822.) The court also looked to pattern jury instructions and Black's Law Dictionary, all of which defined dangerous and deadly weapons, concluding that the term "dangerous or deadly weapon" was well-defined and "clearly established in the law." ( In re R.P., supra, at pp. 567–568, 97 Cal.Rptr.3d 822.) As a result, the court held, "the ‘no-dangerous-or-deadly-weapon’ probation condition [was] sufficiently precise for [the minor] to know what is required of him." ( Id. at p. 568, 97 Cal.Rptr.3d 822.)

In this case, the omission of "dangerous or deadly" does not render the juvenile court's weapons prohibition unconstitutionally vague. The classic statement of what constitutes a dangerous or deadly weapon in California criminal law dates back to People v. Raleigh (1932) 128 Cal.App. 105, 107, 16 P.2d 752 ( Raleigh ), where the defendant appealed his conviction for attempting to rob a haberdashery with an unloaded gun. "There are," the Court of Appeal explained in Raleigh, "first, those instrumentalities which are weapons in the strict sense of the word, and, second, those instrumentalities which are not weapons in the strict sense of the word, but which may be used as such. The instrumentalities falling in the first class, such as guns, dirks and blackjacks, which are weapons in the strict sense of the word and are ‘dangerous or deadly’ to others in the ordinary use for which they are designed, may be said as a matter of law to be ‘dangerous or deadly weapons.’ This is true as the ordinary use for which they are designed establishes their character as such." ( Id. at p. 108, 16 P.2d 752.) In some circumstances, however, "instrumentalities falling in the second class, such as ordinary razors, pocket-knives, hatpins, canes, hammers, hatchets and other sharp or heavy objects" are "capable of being used in a ‘dangerous or deadly’ manner, and it may be fairly inferred from the evidence that [the] possessor [of such an object] intended on a particular occasion to use it as a weapon," thus establishing its character as a weapon as a matter of fact. ( Id. at pp. 108–109, 16 P.2d 752.) Applying this dichotomy, the Raleigh court held that, because the gun used by the defendant in that case was a dangerous or deadly weapon per se, it was not necessary for the trial court to instruct on and submit the issue to the jury for factual determination. ( Id. at pp. 110–111, 16 P.2d 752.) In this case, the juvenile court's approach to the weapons prohibition imposed on Minor begins by listing a number of specific items and instruments that will categorically fall within the prohibition ("guns, knives, clubs, brass knuckles, attack dogs, ammunition"), but then leaves the prohibition open-ended in a manner that could capture other things ("something that looks like a weapon" or "anything that you could use as a weapon or someone else might consider to be a weapon") depending on the circumstances. This generally follows the established Raleigh two-step test for dangerous or deadly weapons. Under that test, the notion that an instrument or object must be either "dangerous or deadly" in order to qualify as a "weapon" is so fundamental that it need not be stated explicitly. (See People v. Pruett (1997) 57 Cal.App.4th 77, 86, 66 Cal.Rptr.2d 750 ["Because the use of [a pocket knife] with the intent to resist arrest or detention necessarily encompasses its use or intended use as a weapon, no definition of ‘weapon’ or ‘deadly weapon’ is required"].) Because the qualifier "dangerous or deadly" inheres in the commonly understood meaning of the term "weapon" (see Black's Law Dict. (10th ed. 2014) p. 1827 ["[a]n instrument used or designed to be used to injure or kill someone"] ), we agree with the Attorney General that it is implicit in the probation condition as phrased by the court. Even without the qualifier Minor seeks, a reasonable person can understand the plain meaning of the term "weapon."

For other reasons, however, we agree with Minor that the prohibition on "possess[ing] anything that [he] could use as a weapon" does not provide adequate notice of the prohibited conduct. First, as worded, the condition is broad enough to include any object that could injure someone, even an ordinary household object, regardless of Minor's intent in possessing it. A condition framed that broadly certainly could accord with the settled meaning of "weapon" and related terms in case law, but it omits an idea that is essential to Raleigh's second category—that of de facto weapons. "[A]n item commonly used for a nonviolent purpose, such as a baseball bat or a table leg, could qualify as a [dangerous or deadly weapon] ... only ‘when the attendant circumstances, including the time, place, destination of the possessor, the alteration of the object from standard form, and other relevant facts indicate[ ] that the possessor would use the object for a dangerous, not harmless, purpose.’ " ( People v. King (2006) 38 Cal.4th 617, 624, 42 Cal.Rptr.3d 743, 133 P.3d 636 ( King ), citation omitted.) Because what is and what is not a de facto weapon turns in part on intent to use the item for a dangerous or deadly purpose, we will order the condition modified to prohibit Minor from possessing any object that he intends to use as a weapon.

Second, the above portion and other portions of the weapons possession prohibition must be modified to include a scienter requirement. "California appellate courts have found probation conditions to be unconstitutionally vague or overbroad when they do not require the probationer to have knowledge of the prohibited conduct or circumstances." ( People v. Kim (2011) 193 Cal.App.4th 836, 843, 122 Cal.Rptr.3d 599.) For example, in Sheena K., our Supreme Court held that, in the absence of an express knowledge requirement, a probation condition limiting association with anyone disapproved of by probation was unconstitutionally vague. ( Sheena K., supra, 40 Cal.4th at pp. 891–892, 55 Cal.Rptr.3d 716, 153 P.3d 282.) Without the addition of an express knowledge requirement, the court reasoned, the ban did not provide the probationer with advance notice as to the persons with whom she could not associate. ( Ibid. ) Where a probation condition suffers from this defect, the appellate court may modify the condition to include the missing knowledge requirement. (See id. at p. 892, 55 Cal.Rptr.3d 716, 153 P.3d 282 ; see also In re Victor L. (2010) 182 Cal.App.4th 902, 912–913, 931, 106 Cal.Rptr.3d 584 ( Victor L. ) [modifying probation condition prohibiting presence where dangerous or deadly weapons, firearms, or ammunition exist to include express knowledge requirement]; People v. Freitas (2009) 179 Cal.App.4th 747, 752–753, 102 Cal.Rptr.3d 51 [modifying probation condition to specify that defendant not knowingly possess guns or ammunition].)

Citing People v. Moore (2012) 211 Cal.App.4th 1179, 150 Cal.Rptr.3d 437 ( Moore ), the Attorney General argues that a probation condition lacking an express scienter requirement is not unconstitutionally vague. So long as a probation condition "clearly specif[ies] what conduct [is] prohibited," Moore holds that "the requirement that a violation of the weapons condition must be willful and knowing adequately protects [the probationer] from being punished for innocent possession." ( Id. at p. 1188, 150 Cal.Rptr.3d 437.) "The addition of an express knowledge requirement would add little or nothing to the probation condition," in this view. ( Ibid. ) Division One of this district and a panel of the Sixth District Court of Appeal recently adopted the same approach. ( People v. Hall (2015) 236 Cal.App.4th 1124, 1134, 187 Cal.Rptr.3d 301 ( Hall ) ["We see no reason why probation conditions would need to articulate mens-rea requirements expressly when criminal statutes need not"]; People v. Contreras (2015) 237 Cal.App.4th 868, 887, 188 Cal.Rptr.3d 698 ( Contreras ) [following Hall ].) These cases appear to presuppose that the requisite element of mens rea for proof of a violation is readily ascertainable in advance. It is not.

The statutes governing revocation of juvenile and adult probation do not specify that only a willful violation can result in revocation. Welfare and Institutions Code section 777, which governs the juvenile court equivalent of probation revocation proceedings in adult criminal cases, specifies only that the probation officer or the prosecuting attorney may file a "notice" that "alleges a violation of a condition of probation not amounting to a crime. The notice shall contain a concise statement of facts sufficient to support this conclusion." ( Welf. & Inst. Code, § 777, subd. (a)(2).) "The facts alleged in the notice shall be established by a preponderance of the evidence at a hearing to change, modify, or set aside a previous order." ( Welf. & Inst. Code, § 777, subd. (c).) Under Penal Code section 1203.2, subdivision (a), which applies to adult probationers, probation may be revoked "if the interests of justice so require and the court, in its judgment, has reason to believe from the report of the probation ... officer or otherwise that the person has violated any of the conditions of his or her supervision, has become abandoned to improper associates or a vicious life, or has subsequently committed other offenses, regardless whether he or she has been prosecuted for such offenses."

Ultimately, the determination whether to revoke probation is committed to the sound discretion of the court. ( People v. Zaring (1992) 8 Cal.App.4th 362, 378, 10 Cal.Rptr.2d 263 ( Zaring ).) While it is an abuse of discretion to revoke probation for conduct over which the probationer has no control ( People v. Cervantes (2009) 175 Cal.App.4th 291, 295, 95 Cal.Rptr.3d 858 [inability of immigration detainee to appear for review hearing not willful]; People v. Galvan (2007) 155 Cal.App.4th 978, 982–984, 66 Cal.Rptr.3d 426 [because defendant was deported immediately following his release from county jail, his failure to report to probation department within 24 hours of release from county jail was not willful] ), the mens rea standard in revocation proceedings is difficult to state with precision beyond that. (See Zaring, supra, 8 Cal.App.4th at p. 379, 10 Cal.Rptr.2d 263 [absent "irresponsibility, contumacious behavior or disrespect for the orders and expectations of the court," probationer's conduct was not willful].) Because " ‘[t]he terms "willful" or "willfully" ... imply "simply a purpose or willingness to commit the [prohibited] act ...," without regard to motive, intent to injure, or knowledge of the act's prohibited character ’ " ( Hall, supra, 236 Cal.App.4th at p. 1133, 187 Cal.Rptr.3d 301, italics added, quoting In re Jerry R. (1994) 29 Cal.App.4th 1432, 1438, 35 Cal.Rptr.2d 155 ; see Pen. Code, § 7, item 1), the standard offers little protection against unwitting violation.

Nor does it help to look beyond the statutes for case law construction of what "willful" means. " ‘[W]illful’ is a word ‘of many meanings, its construction often being influenced by its context.’ " ( Screws v. United States (1945) 325 U.S. 91, 101, 65 S.Ct. 1031, 89 L.Ed. 1495, quoting Spies v. United States (1943) 317 U.S. 492, 497, 63 S.Ct. 364, 87 L.Ed. 418.) "Few areas of criminal law pose more difficulty than the proper definition of the mens rea required for any particular crime." ( United States v. Bailey (1980) 444 U.S. 394, 403, 100 S.Ct. 624, 62 L.Ed.2d 575.) "For several centuries (at least since 1600) the different common law crimes have been so defined as to require, for guilt, that the defendant's acts or omissions be accompanied by one or more of the various types of fault (intention, knowledge, recklessness or—more rarely—negligence)[.]" (1 LaFave, Substantive Criminal Law (2d ed. 2003) § 5.5, p. 381.) In some circumstances, the mens rea required to sustain a criminal conviction is simply conscious carrying out of the prohibited act, while in other circumstances some level of awareness of wrongdoing will be required. (See Elonis v. United States (2015) 575 U.S. ––––, ––––, [135 S.Ct. 2001, 2010], 192 L.Ed.2d 1.)

To sharpen the uncertain boundaries of criminal statutes that require proof of nothing more than willfulness as a predicate to violation, courts have often adopted limiting constructions requiring actual knowledge of wrongdoing beyond the basic level of mens rea that is impliedly required for all criminal conduct. (E.g., People v. Garcia (2001) 25 Cal.4th 744, 752, 107 Cal.Rptr.2d 355, 23 P.3d 590 [" ‘willful[ ]’ " omission requires knowledge of legally required act]; People v. Simon (1995) 9 Cal.4th 493, 507, 522, 37 Cal.Rptr.2d 278, 886 P.2d 1271 ["willful" violation of California securities disclosure statute prescribing criminal penalties construed to require finding of knowledge of the falsity or misleading nature of charged misrepresentations or omissions, or criminal negligence in failing to acquire knowledge]; see Liparota v. United States (1985) 471 U.S. 419, 426, 105 S.Ct. 2084, 85 L.Ed.2d 434 [limiting construction requiring that defendant had actual knowledge that his conduct was unauthorized or illegal "is particularly appropriate where, as here, to interpret the statute otherwise would be to criminalize a broad range of apparently innocent conduct"].)

It is true, as the panel in Hall recently observed, there is no requirement that criminal statutes expressly set forth a mens rea element. ( Hall, supra, 236 Cal.App.4th at p. 1134, 187 Cal.Rptr.3d 301.) But it is also true that courts often interpret statutes to require some degree of knowledge of wrongdoing where the governing statutory language is silent—as is the case in Welfare and Institutions Code section 777 and Penal Code section 1203.2 —with respect to the requisite level of culpable intent. Over the last two decades, our Supreme Court has decided a series of cases addressing what level of "guilty knowledge" must be shown to support a conviction in cases where the statute at issue is silent on that issue. In the most recent of these cases, Stark v. Superior Court (2011) 52 Cal.4th 368, 128 Cal.Rptr.3d 611, 257 P.3d 41 ( Stark ), the Court explained that "we have construed criminal statutes to include a guilty knowledge requirement even though the statutes did not expressly articulate such a requirement.... [I]n some cases we have required actual knowledge of the material facts that demonstrate wrongful intent. In other cases, we have concluded that actual knowledge or some form of negligence in failing to know the material facts is required." ( Stark, supra, 52 Cal.4th at p. 393, 128 Cal.Rptr.3d 611, 257 P.3d 41 ; see People v. Salas (2006) 37 Cal.4th 967, 974–975, 981, 38 Cal.Rptr.3d 624, 127 P.3d 40 ; King, supra, 38 Cal.4th at pp. 622–623, 42 Cal.Rptr.3d 743, 133 P.3d 636 ; People v. Coria (1999) 21 Cal.4th 868, 878, 89 Cal.Rptr.2d 650, 985 P.2d 970 ; In re Jorge M. (2000) 23 Cal.4th 866, 872, 887, 98 Cal.Rptr.2d 466, 4 P.3d 297 ; People v. Rubalcava (2000) 23 Cal.4th 322, 332, 96 Cal.Rptr.2d 735, 1 P.3d 52 ( Rubalcava ); People v. Garcia, supra, 25 Cal.4th at p. 752, 107 Cal.Rptr.2d 355, 23 P.3d 590.)

Two of the cases in this line of precedent, both involving illegal weapons possession under former Penal Code section 12020, subdivision (a)(1), are pertinent here. In King, supra, 38 Cal.4th at p. 620, 42 Cal.Rptr.3d 743, 133 P.3d 636, the Court held that to secure a conviction for possession of a short-barreled firearm, the prosecution "must prove the possessor's knowledge of the weapon's illegal characteristics." And in Rubalcava, supra, 23 Cal.4th at pp. 328, 332, 96 Cal.Rptr.2d 735, 1 P.3d 52, the court held that, even though conviction for possession of a concealed dirk or dagger does not require specific intent to stab anyone with such an instrument, the "defendant must still have the requisite guilty mind: that is, [he] must knowingly and intentionally carry concealed upon his or her person an instrument ‘that is capable of ready use as a stabbing weapon.’ [Citation.] A defendant who does not know that he is carrying the weapon or that the concealed instrument may be used as a stabbing weapon is therefore not guilty of violating [former Penal Code] section 12020." Striking a theme introduced by the high court in Staples —which involved failure to register a firearm—in both King and Rubalcava the California Supreme Court found it notable that the possessory crime at issue covered " ‘ "traditionally lawful conduct." ’ " ( Rubalcava, supra, 23 Cal.4th at p. 331, 96 Cal.Rptr.2d 735, 1 P.3d 52 ; see King, supra, 38 Cal.4th at p. 624, 42 Cal.Rptr.3d 743, 133 P.3d 636.) When that is the case, as it is here, given the breadth of what might be considered a "weapon," see ante at footnote 4, a requirement of actual knowledge of the character of the weapon is appropriate to avoid criminalizing innocent conduct. (See King, supra, 38 Cal.4th at p. 626, 42 Cal.Rptr.3d 743, 133 P.3d 636 ["[i]t is highly unlikely that the Legislature intended that a person possessing an item listed in [former Penal Code section 12020, subdivision (a)(1) ] for its lawful, utilitarian purpose, but unaware of the characteristic that makes possession of the item illegal, would nevertheless be guilty of violating [former Penal Code section 12020, subdivision (a)(1) ]"].)

Accordingly, we will require modification to add a scienter requirement. With the other clarifications we have required, a probationer can easily understand the type of conduct that is proscribed (i.e., he may not possess weapons). But the difficulty of defining with perfect clarity every potential item that might be considered a weapon illustrates why more warning is necessary. To provide adequate protection against unwitting violations, the probationer must engage in the proscribed conduct knowingly (i.e., with actual intent and understanding that he possesses something constituting a weapon). Particularly since there is a conditional liberty interest at stake, we think the addition of an express knowledge requirement making the scope of the prohibited conduct clear in advance to all who may be involved—to probationers, to law enforcement officers, to probation departments, and to juvenile courts—best comports with due process. (See Victor L., supra, 182 Cal.App.4th at pp. 912–913, 106 Cal.Rptr.3d 584 [modifying probation condition barring probationer from remaining in location where weapons are present to add explicit knowledge requirement, and explaining "[d]ue process requires ... that the probationer be informed in advance whether his conduct comports with or violates a condition of probation"].)

III. DISPOSITION

The weapon probation condition is modified to read: "The minor shall: ... Not knowingly possess weapons of any kind, which means no guns, knives, clubs, brass knuckles, attack dogs, ammunition, or something that looks like a weapon. In addition, you are not to knowingly possess anything that you intend to use as a weapon or that you know someone else might consider to be a weapon." As so modified, the judgment is affirmed.

We concur:

Ruvolo, P.J.

Reardon, J.