¶1 The State appeals, arguing that the trial court erred in dismissing, on mandatory joinder and *98double jeopardy grounds, James Green’s charge for failure to register as a sex offender. We affirm.

FACTS

¶2 Green, a convicted level II sex offender, is required to register every 90 days under RCW 9A.44.130. He registered as required with the Pacific County sheriff on April 9,2007, but he failed to report again until April 29, 2008.

¶3 The State charged Green with one count of failing to register as a sex offender, with the date of the alleged offense as “on or about July 9, 2007.” Clerk’s Papers (cause number 08-1-00054-9) (CP) at 7; RCW 9A.44.130(7). In September 2008, the trial court held a bench trial and found Green not guilty because the State failed to prove an “essential element” of the offense that Green had a “fixed residence” on or about July 9, 2007. CP at 28.

¶4 By amended information, the State again charged Green with one count of failing to register as a sex offender, with the date of the alleged offense listed as “on or about October 8, 2007.” CP at 12. He moved to dismiss, arguing that the State’s filing of another case against him for the same offense violated the mandatory joinder rule under CrR 4.3.1 and the constitutional prohibition against double jeopardy.

¶5 The trial court agreed with Green and dismissed the case. The State appeals.

ANALYSIS

¶6 The State contends that the trial court erred in holding that mandatory joinder and double jeopardy barred Green’s prosecution. The State further contends that under the separation of powers doctrine, a trial court may not prevent the prosecutor from exercising its discretion in *99making charging decisions. On the double jeopardy argument, we disagree.1

¶7 The double jeopardy clauses of the United States and Washington State Constitutions protect a defendant from multiple convictions for the same crime. U.S. Const, amend. V; Wash. Const, art. I, § 9; State v. Tvedt, 153 Wn.2d 705, 710, 107 P.3d 728 (2005). Double jeopardy protections are also implicated where the State seeks to subject the defendant to a second trial for the same offense. See United States v. Scott, 437 U.S. 82, 87-88, 98 S. Ct. 2187, 57 L. Ed. 2d 65 (1978). We review constitutional challenges de novo. State v. Jones, 159 Wn.2d 231, 237, 149 P.3d 636 (2006).

¶8 In order to determine whether a defendant’s rights against double jeopardy were violated, we must determine what “unit of prosecution” the legislature intended to be the punishable act. State v. Adel, 136 Wn.2d 629, 634, 965 P.2d 1072 (1998). The “unit of prosecution” refers to the scope of the criminal act. Adel, 136 Wn.2d at 634. Our analysis requires that we look first to the statute’s plain language and, if necessary, to the legislative history. State v. Durrett, 150 Wn. App. 402, 406, 208 P.3d 1174 (2009).2 But if the legislature’s intent is unclear, the rule of lenity requires us to construe any ambiguities in the defendant’s favor. State v. Bobic, 140 Wn.2d 250, 261-62, 996 P.2d 610 (2000).

¶9 RCW 9A.44.130 imposes a general duty on sex offenders to register. And RCW 9A.44.130(7), which relates specifically to Green’s duty, states in pertinent part:

All offenders who are required to register pursuant to this section who have a fixed residence and who are designated as *100a risk level II or III must report, in person, every ninety days to the sheriff of the county where he or she is registered.

The State charged Green under RCW 9A.44.130(ll)(a), which provides that “[a] person who knowingly fails to comply with any of the requirements of this section is guilty of a class B felony.”

¶10 It is unclear from the statute’s plain language whether the duty to register “in person, every ninety days” establishes the “unit of prosecution” as each 90-day period in which an offender with a fixed residence fails to register or treats the failure as an ongoing course of conduct. RCW 9A.44.130(7). Division One considered a similar question in Durrett and found the statute ambiguous, construing it in the defendant’s favor.3 150 Wn. App. at 410.

¶11 The State argues in part that one of the operative terms in RCW 9A.44.130(1l)(a) is the word “any” which establishes separate discrete violations for each 90-day period Green failed to register. But in Durrett, the court recognized that “any” is often construed to mean “every” and “all” rather than “one.” 150 Wn. App. at 408-09. The State also argues generally that the legislature’s intent in establishing the registration requirements was to assist law enforcement agencies in protecting the public and that construing the statute as creating discrete violations fulfills that intent. And the State noted that under Blockburger v. United States, 284 U.S. 299, 304, 52 S. Ct. 180, 76 L. Ed. 306 (1932), the 90-day difference between each charge is “more than sufficient to establish the second crime as separate and distinct.” Appellant’s Br. at 17-18. But Block-burger articulated that in the case of a single “ ‘impulse,’ ” only “ ‘one indictment lies.’ ” 284 U.S. at 302 (quoting I *101Francis Wharton, A Treatise on Criminal Law § 34 (11th ed. 1912)). The State’s arguments do not persuade us.

¶12 Green recites a few statutory provisions to support his argument that we should construe his failure to register as a continuing course of conduct. In order to ensure that a convicted sex offender avoiding detection by failing to register could not outrun the statute of limitations, the legislature established that “[u]nless relieved of the duty to register pursuant to this section, a violation of RCW 9A.44.130 is an ongoing offense for purposes of the statute of limitations under RCW 9A.04.080.” RCW 9A.44.140(6). And under RCW 9A.44.130(4)(c), the legislature explicitly established that “[a]n arrest on charges of failure to register, service of an information, or a complaint for a violation of this section, or arraignment on charges for a violation of this section, constitutes actual notice of the duty to register.”4

¶13 In light of these statutory provisions and Division One’s reasoning and holding in Durrett, we construe the duty to register every 90 days as creating an ongoing course of conduct that cannot support separate charges. Furthermore, the facts of this case support our “unit of prosecution” determination. In this instance, Green first violated RCW 9A.44.130(ll)(a) on or about July 9,2007. He committed an ongoing and continuing offense from that point until he registered again on April 29, 2008. It was not until after April 29 that the State charged him for the first time.

¶14 The State’s argument that the failure to register for each 90-day period after Green failed to register constitutes a separate charge is based on a flawed reading of RCW 9A.44.130. The State may file another charge for new failure to register conduct, so long as the continuing course of conduct of a prior failure to register has ended.

*102¶15 The trial court properly dismissed the charge for failure to register.5

¶16 Affirmed.

¶17 (dissenting) — I respectfully dissent from the majority’s view that the entire period in which James Green failed to report constituted “an ongoing course of conduct that cannot support separate charges.” Majority at 101.1 would reverse and remand for trial.

I. Multiple Violations; No Double Jeopardy

¶18 The United States and Washington State Constitutions protect defendants from double jeopardy. U.S. Const. amend. V; Wash. Const, art. I, § 9. It is impermissible for a defendant to be convicted more than once for the same crime under the same statute. State v. Tvedt, 153 Wn.2d 705, 710, 107 P.3d 728 (2005). But when facts show multiple violations of the same crime, a defendant is properly charged with multiple violations. Therefore, the double jeopardy question focuses on what “unit of prosecution” the legislature intends as the punishable act under a given statute. State v. Westling, 145 Wn.2d 607, 610, 40 P.3d 669 (2002); In re Pers. Restraint of Davis, 142 Wn.2d 165, 172, 12 P.3d 603 (2000). The proper unit of prosecution revolves around statutory interpretation and legislative intent. State v. Adel, 136 Wn.2d 629, 634, 965 P.2d 1072 (1998). If the legislature’s intent is unclear, the court will construe hypothetical ambiguities in the defendant’s favor in accor*103dance with the rule of lenity. State v. Bobic, 140 Wn.2d 250, 261-62, 996 P.2d 610 (2000). Such is not the case here, however.

¶19 To protect the public from convicted sex offenders released back into the community,6 our legislature requires them to register their locations with their respective county sheriffs and to report periodically to confirm their locations. RCW 9A.44.130(4)(b) expressly provides, “Failure to register within the time required under this section constitutes a per se violation of this section and is punishable as provided in subsection (11) of this section.”7 (Emphasis added.) The legislature thus focuses on “a” failure to register within the required 90-day period as “a” single violation. The statute is not ambiguous nor is the legislature’s intent unclear. In my view, therefore, it is unreasonable to read this plain language as an indication that the legislature intended to punish a sex offender who repeatedly flaunts the law by repeatedly failing to report for multiple 90-day periods the same as a sex offender who fails to report only once.

*104¶20 My view is consistent with People v. Meeks, in which the California Court of Appeals rejected an argument similar to Green’s in a case involving an analogous California statute requiring a sex offender to register annually on his birthday and also when he changed his address:

Defendant contends that his conviction for failing to register within five days of his birthday should be stricken because [California Penal Code] section 290’s registration requirements are continuing offenses. He argues: “Once a registrant has willfully failed in the legal duty to update that registration upon birthday or change of address, that state of law violation continues until terminated by some significant event, registration, arrest, death, etc. While a former registrant is in that state of willful failure to comply, the passage of other events requiring registration cannot be new offenses because the existing violation had not yet been completed. That a second birthday passes or another change of residence occurs is not a new offense, but merely a continuation of the state of unlawfulness.” We are not persuaded.

Failure to register under section 290 is a continuing offense (§ 290, subd. (g)(8); Wright v. Superior Court (1997) 15 Cal.4th 521, 528 [63 Cal.Rptr.2d 322, 936 P.2d 101]), that is, one “marked by a continuing duty in the defendant to do an act which he fails to do. The offense continues as long as the duty persists and there is a failure to perform that duty.” (Id. at p. 525.) But simply because the Legislature intended that a violation of section 290 be a continuing offense does not mean that a defendant cannot be convicted and punished for new and separate violations of section 290 as he continues to ignore the law.

The Legislature has found it imperative for the safety of society that the location of sex offenders be known to law enforcement at all times,[8] thus requiring defendants subject *105to section 290 to reregister annually and upon a change of location serves that purpose by providing law enforcement with updated information through which it may track these defendants. It would ill serve the purpose of section 290 to provide defendants who fail to register with blanket immunity from prosecution for all but a single failure to register. A defendant who knows that he is subject to prosecution for each violation of the registration requirement is more likely to comply in order to avoid additional punishment and is more likely to become visible again to law enforcement. Thus visible, he arguably is less likely to repeat his sexual crimes. By requiring defendants to register annually and with every change of residence, it was no doubt the Legislature’s intent to treat each violation of the registration requirements as a separate, continuing offense in order to encourage compliance with the law and to ensure to the extent possible that a sex offender’s whereabouts remain known.

People v. Meeks, 123 Cal. App. 4th 695, 702-03, 20 Cal. Rptr. 3d 445 (2004) (emphasis added) (second alteration in original).

¶21 The California court acknowledged, however, “Had the prosecution charged a separate offense for each day of defendant’s failure to register when he changed his address, the defendant would then have been subjected improperly to multiple convictions for a single criminal act.” Meeks, 123 Cal. App. 4th at 703 (emphasis added). But the court clearly distinguished and held lawful “[defendant's separate convictions for failure to register upon a change of address and to register annually on his birthday....” Meeks, 123 Cal. App. 4th at 703.

Failure to register within five days of defendant’s birthday occurred after December 8, 1998, and again after December 8, 1999, and every year thereafter. Although the periods for each of these offenses overlap somewhat and the objective of each is *106the same, it cannot reasonably be argued that defendant can be punished only once for each successive failure to register. . . .

“[T]he purpose of [California Penal Code] section 654 ‘is to insure that a defendant’s punishment will be commensurate with his culpability.’ ”... [F]ailure to punish defendant for each failure to register would violate this purpose. A defendant who . . . repeatedly allows a birthday to pass without registering, is surely more culpable than one who fails to register following only one triggering event. Section 654 does not prohibit the multiple punishments imposed in this case.

Meeks, 123 Cal. App. 4th at 705-06 (emphasis added) (first alteration in original) (quoting People v. Latimer, 5 Cal. 4th 1203, 1211, 858 P.2d 611, 23 Cal. Rptr. 2d 144 (1993)).

¶22 In Meeks, the repeating registration period was one year under the California sex offender registration statute.9 Here, the period is 90 days under Washington’s sex offender registration statute.10 But the same rationale should apply to both situations. Clearly our legislature’s intent in enacting our sex offender statute was similar to the intent of California’s statute. As Meeks describes above, the statute is intended to keep convicted sex offenders who have been released into the community visible to law enforcement by requiring periodic registration and re-registration, and to encourage offenders to comply with registration requirements by punishing more harshly those who repeatedly fail to register over specified periods of time. To hold that Green’s successive violations of Washington’s registration statute were merely one unit of prosecution, susceptible to one conviction and one punishment, leads to a result that our legislature could not have intended, namely that Green’s repeated failures to register for multiple 90-day periods over the course of more than one year would leave him no more culpable than one who failed only once to register during a single 90-day period.

*107¶23 Green’s multiple failures to register during successive 90-day periods should constitute multiple units of prosecution because they are separate and distinct offenses whether analyzed under double jeopardy or for mandatory joinder principles. I would hold that the State’s prosecution and conviction of Green for failing to register during the second 90-day period did not expose him to a second prosecution for the same offense and, therefore, did not constitute double jeopardy.

II. Mandatory Joinder

¶24 Although the majority reaches its decision solely on double jeopardy grounds, the trial court dismissed on both double jeopardy and mandatory joinder grounds. Therefore, I also address mandatory joinder in this dissent. As the State argued, a sex offender who fails to register for two consecutive 90-day periods commits two separate offenses that are not “related” for purposes of the mandatory joinder rule; therefore, the trial court erred by granting Green’s motion to dismiss under CrR 4.3.1(b)(3) for failure to join the July 9 and October 8 charges.

A. Not “Related Offenses”

¶25 Under the mandatory joinder rule, two or more offenses must be joined if they are “related offenses.” CrR 4.3.1(b)(3).11 Offenses are “related” if they are within the jurisdiction and venue of the same court and are based on *108the “same conduct.”12 CrR 4.3.1(b)(1). As our Supreme Court explained in State v. Lee, mandatory joinder is not required because offenses are based upon a series of acts constituting a single scheme or plan, but rather because a series of acts represents a single criminal incident or episode of the “same conduct.” 132 Wn.2d 498, 503-04, 939 P.2d 1223 (1997). The Supreme Court noted that a series of acts constituting the same criminal episode could span many hours or even days; however, “[cjlose temporal . . . proximity . . . will often be present.” Lee, 132 Wn.2d at 503-04. But the State’s awareness of additional charges does not require mandatory joinder under the rule.13 Lee, 132 Wn.2d at 505.

¶26 Here, the two criminal episodes for which the State charged Green were 90 days apart (July 9 to October 8, 2007). Although Green’s violations consisted of the same criminal activity, they did not derive from the “same conduct” because they encompassed more than one episode or incident of failure to register. Therefore, the multiple 90-day periods were not “related” for purposes of the mandatory joinder rule under Lee.

B. “Ends of Justice”

¶27 Even assuming, without deciding, that Green’s multiple sequential failures to register were “related offenses” *109for purposes of the mandatory joinder rule, remanding for trial of the erroneously dismissed charge meets the “ends of justice” exception. CrR 4.3.1(b)(3). Green’s acquittal on the initial charge resulted from the trial court’s mistaken interpretation of the statutory elements of failure to register. It is undisputed that Green failed to register as a sex offender for 385 days and that there were no evidentiary deficiencies in the State’s proof that he failed to register during the first 90-day period. Nevertheless, the trial court acquitted because it found that the State had failed to prove what it characterized as an “essential element” of the offense, namely, that Green had a “fixed residence” on or about July 9, 2007. Clerk’s Papers (CP) at 43. But as the trial court later acknowledged, Peterson held that the State is not required to prove “a fixed residence” as an element of the crime of failure to register.14

¶28 The trial court’s legal error resulted in an erroneous acquittal, which the State could not remedy by appealing.15 Thus, the State’s only option for following the legislature’s mandate and holding Green accountable for his persistent failures to register as a sex offender was to charge him with a second, separate violation, this time for failing to register for a different 90-day period. Here, “the ends of justice” were “defeated” when the trial court granted Green’s motion to dismiss. CrR 4.3.1(b)(3); see, e.g., State v. Ramos, 124 Wn. App. 334, 339, 101 P.3d 872 (2004) (Concerning application of “ends of justice” exception, Division One of our court noted, “ ‘[W]e can conceive of a scenario where through no fault on its part the granting of a motion to dismiss under the rule would preclude the State from *110retrying a defendant or severely hamper it in further prosecution____’ ” (quoting State v. Carter, 56 Wn. App. 217, 223, 783 P.2d 589 (1989))).16

¶29 I would reverse the trial court’s dismissal of the charge and remand for reinstatement and trial; therefore, I respectfully dissent.