Fisher, Associate Judge:
Appellant George Fadero challenges the trial courts denial of his D.C. Code § 23-110 (2012 Repl.) motion for post-conviction relief. We affirm.
I.
This case reaches us for the third time. We summarized the facts in Fadero v. United States , 59 A.3d 1239, 1242-44 (D.C. 2013) ( Fadero I ), and do so only briefly here. On February 12, 2011, a Metropolitan Police Department Officer stopped appellant for a traffic violation. As the officer was walking away from appellant, he turned around to see appellants van slowly moving toward him in reverse. The van hit the officer, knocking him to the ground, and causing him injuries. It then sped away from the scene.
The government charged appellant with several offenses based on this conduct, including felony assault on a police officer while armed (APOWA). A jury convicted appellant of four of the charged offenses, including APOWA. We affirmed all convictions, except one, which we held merged with the APOWA count. While that appeal was pending, appellant collaterally attacked the conviction through a § 23-110 motion, claiming ineffective assistance of trial counsel. Fadero v. United States , No. 13-CO-479, Mem. Op. & J. at 1, 92 A.3d 334 (D.C. Apr. 23, 2014) ( Fadero II ). The trial court denied the motion without a hearing, and we affirmed that decision, too. Id. at 4, 6. Appellant filed this second § 23-110 motion pro se . The trial court denied it without a hearing and this appeal followed.
II.
This appeal focuses on appellants APOWA conviction, an offense that derives from two statutory provisions. See Fadero I , 59 A.3d at 1242 n.1 (defining the elements of APOWA). The first is felony assault on a police officer, D.C. Code § 22-405 (c), which makes it illegal to (1) assault a person when the defendant (2) knew or should have known that the victim was a [law enforcement] officer and (3) caused a significant bodily injury to the law enforcement officer, or committed a violent act that create[d] a grave risk of causing significant bodily injury to the officer. Id. (quoting § 22-405 (c) ) (alterations in original). The second predicate is D.C. Code § 22-4502, which provides that defendants may face additional punishment if they commit a crime of violence ... when armed with or having readily available ... [a] dangerous or deadly weapon.
III.
Appellant principally argues that the phrase grave risk of causing significant bodily injury, incorporated in § 22-405 (c), is unconstitutionally vague in light of Johnson v. United States , --- U.S. ----, 135 S.Ct. 2551, 192 L.Ed.2d 569 (2015). In that case, the Supreme Court considered a provision of the Armed Career Criminal Act (ACCA) that defined a violent felony, in relevant part, as any crime punishable by imprisonment for a term exceeding one year ... that ... is burglary, arson, or extortion, involves use of explosives, or otherwise involves conduct that presents a serious potential risk of physical injury to another . 135 S.Ct. at 2555-56 (quoting 18 U.S.C. § 924 (e)(2)(B) (2012) ) (first alteration in original). The Court referred to the italicized language as the residual clause and held it void for vagueness. Id. at 2556, 2557. Appellant analogizes the grave risk language in § 22-405 (c) to the serious potential risk of physical injury language in the ACCA and contends that if the latter phrase offends due process, the former must as well.
We disagree. The holding in Johnson turned on the manner in which that sentencing enhancement provision operated. Whether the residual clause applied depended on whether the given offense created a sufficiently high risk of injury to others. See 18 U.S.C. § 924 (e)(2)(B)(ii). Yet, the Supreme Court had held that the relevant ACCA provision, 18 U.S.C. § 924 (e)(2)(B)(ii), required a categorical approach. Taylor v. United States , 495 U.S. 575, 600, 110 S.Ct. 2143, 109 L.Ed.2d 607 (1990). In other words, judges were barred from assessing an offenses potential for harm based on the way a defendant committed it. Johnson , 135 S.Ct. at 2557. Instead, § 924 (e)(2)(B)(ii) required judges to imagine how the idealized ordinary case of the crime subsequently play[ed] out and evaluate whether that abstraction present[ed] a serious potential risk of physical injury. Id. at 2557-58. Defining the ordinary way a crime unfolded was a highly subjective exercise-as the Court noted, the ordinary instance of witness tampering [could] involve offering a witness a bribe ... [o]r threatening a witness with violence-and as a result, courts measured risk from a speculative starting point. Id. In holding the residual clause unconstitutionally vague, the Court emphasized this peculiar context. Id.
Section 22-405 (c) does not pose the same concerns. Whether a defendant commit[ted] a violent act that create[d] a grave risk of causing significant bodily injury to the officer is a question of fact. See, e.g. , Mobley v. United States , 101 A.3d 406, 421 (D.C. 2014) (holding trial judge committed plain error by not instruct[ing] the jury that to return a guilty verdict on the APOWA offenses, it must find that the defendant caused a significant bodily injury or created a grave risk thereof (emphasis added) ). It turns on the fact-finders assessment of the defendants actual conduct and does not require judges to measure the risk posed by reference to abstractions. See id. Demonstrating this point, on appellants direct appeal, we approved the judges jury instruction on APOWAs significant bodily injury element, Fadero I , 59 A.3d at 1248, a holding we could only have reached if we assumed that element posed a jury question-that is, one resolved by apply[ing] the law to th[e] facts. United States v. Gaudin , 515 U.S. 506, 514, 115 S.Ct. 2310, 132 L.Ed.2d 444 (1995). Similarly, when we held the evidence sufficient to establish that appellant created a grave risk of harm to the officer, we based our holding on the risks posed by appellants behavior rather than the potential for harm inherent in the ordinary APOWA incident. Fadero I , 59 A.3d at 1252. As appellants own case illustrates, § 22-405 (c) does not share the constitutional defects the Supreme Court perceived in the residual clause.
Moreover, § 22-405 (c) is precisely the type of statute the Johnson Court assumed its decision would not affect. The Court stated that [a]s a general matter, we do not doubt the constitutionality of laws that call for the application of a qualitative standard such as substantial risk to real world conduct. Johnson , 135 S.Ct. at 2561. Section 22-405 (c)s grave risk language fits comfortably in this category-indeed, the Court specifically highlighted the phrase grave risk as one it did not view as inherently vague. Id. Because § 22-405 (c)s grave risk standard differs from the residual clause in ways the Court deemed [c]ritical[ ], appellants Johnson challenge fails. Id. at 2557.
IV.
We address appellants remaining arguments summarily. First, appellant challenges the sufficiency of the evidence supporting his convictions for APOWA, Fleeing from Scene of Accident after Causing Personal Injury ( D.C. Code § 50-2201.05 (a)(1) (2001) ), and Fleeing from a Law Enforcement Officer in a Motor Vehicle ( D.C. Code § 50-2201.05b (b)(2) (2001) ). On direct appeal, appellant already challenged the sufficiency of the evidence supporting the first two convictions and lost. Fadero I , 59 A.3d at 1251-52. It is well-settled that where an appellate court has disposed of an issue on appeal, it will not be considered afresh on collateral attack in a trial court of the same judicial system, absent special circumstances. Doepel v. United States , 510 A.2d 1044, 1045-46 (D.C. 1986). Appellant has identified no such special circumstances; accordingly, the trial court properly held that the sufficiency challenges to the first two convictions were procedurally barred.
With respect to the third conviction, appellant did not raise a sufficiency challenge on direct appeal even though the argument was available to him. See Fadero I , 59 A.3d at 1251-52. Consequently, he may only assert the claim in this § 23-110 proceeding if he can establish cause for and prejudice from his failure to make the argument previously. ( Charles ) Thomas v. United States , 772 A.2d 818, 824 (D.C. 2001). Appellant has not attempted such a showing, and, as a result, the trial court did not err in rejecting the third sufficiency challenge on procedural grounds.
Next, appellant argues that § 22-405 (c) does not qualify as a crime of violence under § 22-4502 because crimes of violence require intentional conduct and, he asserts, § 22-405 (c) does not. Appellant relies primarily on federal cases for the supposed rule that whether an offense qualifies as a crime of violence depends on its intent element; however, the United States and the District of Columbia define crime of violence in very different ways. Colter v. United States , 37 A.3d 282, 283 (D.C. 2012). While the United States Code defines such crimes by their characteristics, see 18 U.S.C. § 16, the D.C. Code identifies them by reference to a list of the offenses so designated. Id. (describing the relationship between § 22-4502 and § 23-1331 (4), the provision that enumerates crimes of violence). [A]ssault on a police officer (felony)- D.C. Code § 22-405 (c) -appears on that list. D.C. Code § 22-1331 (4). Therefore, it qualifies as a crime of violence regardless of whether it would satisfy the federal definition.
Finally, appellant argues that the government violated article I, § 1 of the United States Constitution (All legislative Powers herein granted shall be vested in a Congress of the United States....) by charging him with APOWA, an offense appellant contends the legislature never established. Appellant did not raise this challenge to the indictment before trial. That makes the contention untimely, see Super. Ct. Crim. R. 12 (b)(3)(B)(v), and appellant has not attempted to excuse his delay by showing good cause, see id. at 12 (c)(3). Accordingly, the trial court did not err in holding the argument procedurally barred. Cf. Ko v. United States , 722 A.2d 830, 836 n.17 (D.C. 1998) (By failing to assert the claim of duplicity [in the indictment] at trial, Ko waived it.).
Even if appellant had followed proper procedures, his claim would still fail. In essence, appellant contends that the legislature did not intend prosecutors to combine D.C. Code §§ 22-405 (c) and - 4502 (a)(1) into a single, chargeable offense. To the contrary, by enacting § 22-4502, the legislature authorized increased punishment for a broad category of offenses committed in an aggravated manner. It did so by add[ing] an additional element, i.e. , while armed with or having readily available a dangerous weapon, to certain underlying offenses. ( Michael ) Thomas v. United States , 602 A.2d 647, 653 n.18 (D.C. 1992). Thus, it was the legislature, not the executive branch, that established aggravated offenses such as APOWA, murder while armed, and armed robbery. Consistent with that plain reading, this court treats such offenses no differently from any others. See, e.g. , Robinson v. United States , 100 A.3d 95, 105 (D.C. 2014) (applying traditional aiding and abetting liability principles to while armed offenses); Pope v. United States , 739 A.2d 819, 821 (D.C. 1999) (discussing the offense of assault with intent to kill while armed (AWIKWA), [a] violation of D.C. Code §§ 22-503, - 3202 [the predecessor of -4502] (emphasis added) ). Accordingly, we reject appellants premise: APOWA is an offense created by the legislature and, therefore, the prosecutor could not contravene legislative will-let alone usurp legislative powers-by charging him with it.
V.
Appellants arguments have no merit. Thus, we affirm the trial courts denial of his § 23-110 motion.
So ordered.
After appellant lost on direct appeal, the Council of the District of Columbia repealed, amended, and recodified this provision as § 50-2201.05 (c) (2014 Repl.).
Moreover, appellant did not explain why the evidence at trial was insufficient, making his argument too perfunctory for our review. See Comford v. United States , 947 A.2d 1181, 1188 (D.C. 2008) (quoting United States v. Zannino , 895 F.2d 1, 17 (1st Cir. 1990) ).
The trial court held this claim procedurally barred, and the government urges that we do the same. We do not address the procedural arguments because we choose to reject the claim on the merits. In doing so, we exercise our authority to affirm the trial courts judgment on alternative ground[s]. James v. United States , 718 A.2d 1083, 1089 (D.C. 1998) (affirming trial courts denial of § 23-110 motion on different rationale than trial court invoked). Resolving appellants claim in this way is not procedurally unfair to him. The government made the dispositive argument in its brief. Appellant could have responded to it but choose not to file a reply brief. Cf. District of Columbia v. Patterson , 667 A.2d 1338, 1347 (D.C. 1995) (disposing of claim based on argument raised in defendants brief to which plaintiff failed to respond in its reply brief).
Appellants argument suffers an additional defect: in relying on U.S. Const. art I, § 1, it assumes that Congress retains exclusive power to legislate for the District of Columbia. This is not so. Under the Home Rule Act, Congress delegated significant legislative authority to the Council of the District of Columbia, including the power to enact new criminal statutes. In re Perrow , 172 A.3d 894, 898 (D.C. 2017) ; see also D.C. Code § 1-203.02 (2012 Repl.).