¶ 1. This is a review of a decision of the court of appeals granting habeas corpus relief and ordering the release of a sexually violent person from commitment under Chapter 980 of the Wisconsin Statutes as a remedy for the failure of the Department of Health and Family Services ("the department") to conduct a timely post-commitment initial reexamination under Wis. Stat. § 980.07 (2001-2002).1 We reverse.
¶ 2. Although we agree with the court of appeals' conclusion that the initial reexamination specified in Wis. Stat. § 980.07 is mandatory rather than directory, it does not follow that the extraordinary remedy of release pursuant to a writ of habeas corpus is proper. Habeas corpus relief is warranted only when the petitioner's liberty is restrained in violation of the constitution or by a court or tribunal lacking jurisdiction, and only when no other remedies are adequate. State ex rel. Haas v. McReynolds, 2002 WI 43, ¶ 12, 252 *724Wis. 2d 133, 141, 643 N.W.2d 771. Here, we need not decide whether the failure to comply with the mandatory statutory timeframe for reexamination affects the constitutionality of the underlying Chapter 980 commitment, or the competency of the court to conduct further proceedings in connection with that commitment. The petitioner has not demonstrated that other available remedies are inadequate. Those remedies include a petition for supervised release pursuant to Wis. Stat. § 980.08, or mandamus and contempt. Because there are adequate alternative remedies, habeas corpus relief in the form of discharge and release from commitment is unwarranted.
I. FACTS AND PROCEDURAL HISTORY
¶ 3. William Marberry was committed as a sexually violent person on July 15, 1998, in Dane County Circuit Court, pursuant to Wis. Stat. § 980.06. According to Wis. Stat. § 980.07(1), the department was required to reexamine Marberry's mental condition within six months of his initial commitment.
¶ 4. The department failed to conduct this reexamination within six months of Marberry's initial commitment. Eleven months after his commitment, on June 15, 1999, Marberry filed a petition for a writ of habeas corpus in Winnebago County Circuit Court seeking discharge and release from the Chapter 980 commitment because he still had not received the initial reexamination required by Wis. Stat. § 980.07(1). On September 9, 1999, the circuit court, the Honorable Robert A. Hawley, denied Marberry's habeas petition, but. ordered the department to promptly conduct the reexamination. Marberry appealed.
¶ 5. The court of appeals certified the case to this court. We accepted the certification and, with one *725justice not participating, divided equally. State ex rel. Marberry v. Macht, 2001 WI 19, 241 Wis. 2d 695, 623 N.W.2d 135 (per curiam). The matter was returned to the court of appeals.
¶ 6. In the meantime, on June 29, 2000, almost two years after his initial commitment and more than nine months after the order from the Winnebago County Circuit Court, the department finally conducted a reexamination of Marberry's mental health under Wis. Stat. § 980.07. The examiner concluded that Marberry's mental disorder had not abated. Marberry received another reexamination, and, in a report dated January 8, 2002, was again found to be unfit for release.2
¶ 7. Subsequent to these findings, the court of appeals reversed the circuit court, holding that the six-month timeframe in Wis. Stat. § 980.07(1) for an initial reexamination is mandatory and that Marberry was entitled to release from his Chapter 980 commitment as a remedy. See State ex rel. Marberry v. Macht, 2002 WI App 133, 254 Wis. 2d 690, 648 N.W.2d 522. We granted the state's petition for review, and now reverse.
II. STANDARD OF REVIEW
¶ 8. We apply a de novo standard of review to legal issues arising in the context of a petition for habeas corpus. State ex rel. Hager v. Marten, 226 Wis. 2d 687, *726693-94, 594 N.W.2d 791 (1999). This habeas petition arises in the context of a Chapter 980 commitment and presents an issue of statutory interpretation. Statutory interpretation is a legal issue that we review de novo. In re Commitment of Curiel, 227 Wis. 2d 389, 404, 597 N.W.2d 697 (1999); In re Commitment of Sprosty, 227 Wis. 2d 316, 323, 595 N.W.2d 692 (1999); State v. R.R.E., 162 Wis. 2d 698, 706-07, 470 N.W.2d 283 (1991).
III. DISCUSSION
¶ 9. Chapter 980 governs the involuntary commitment of individuals who have been adjudicated as "sexually violent person[s]." See Wis. Stat. § 980.02(2). A "sexually violent person" is a person who has been convicted, adjudicated delinquent, or found not guilty by reason of mental disease or defect of a sexually violent offense and "is dangerous because he or she suffers from a mental disorder that makes it substantially probable that the person will engage in acts of sexual violence." Wis. Stat. § 980.01(7). If a circuit court or a jury determines that a person is a sexually violent person within the meaning of Chapter 980, "the court shall order the person to be committed to the custody of the department for control, care and treatment until such time as the person is no longer a sexually violent person."3 Wis. Stat. § 980.06.
¶ 10. Chapter 980 provides for periodic reexaminations of the committed person's status as a sexually violent person:
*727If a person has been committed under s. 980.06 and has not been discharged under s. 980.09, the department shall conduct an examination of his or her mental condition within 6 months after an initial commitment under s. 980.06 and again thereafter at least once each 12 months for the purpose of determining whether the person has made sufficient progress for the court to consider whether the person should be placed on supervised release or discharged. At the time of a reexamination under this section, the person who has been committed may retain or seek to have the court appoint an examiner as provided in s. 980.03(4).
Wis. Stat. § 980.07(1).4
¶ 11. In addition to the periodic reexaminations required by Wis. Stat. § 980.07(1), persons committed under Chapter 980 may petition for supervised release into the community:
Any person who is committed under s. 980.06 may petition the committing court to modify its order by authorizing supervised release if at least 18 months have elapsed since the initial commitment order was entered or at least 6 months have elapsed since the most recent release petition was denied or the most recent order for supervised release was revoked. The director of the facility at which the person is placed may file a petition [for supervised release] under this subsection on the person's behalf at any time.
*728Wis. Stat. 980.08U).5
¶ 12. Within 20 days of the receipt of a petition for supervised release, the court "shall appoint one or more examiners having the specialized knowledge determined by the court to be appropriate, who shall examine the person and furnish a written report of the examination to the court within 30 days after appointment." Wis. Stat. § 980.08(3). The court must hear the petition within 30 days of the filing of the report, unless the petitioner waives the time limit. Wis. Stat. § 980.08(4). The statute provides that "[t]he court shall grant the petition [for supervised release] unless the state proves by clear and convincing evidence that the person is still a sexually violent person and that it is still substantially probable that the person will engage in acts of sexual violence if the person is not continued in institutional care." Id.
¶ 13. Chapter 980 also provides that a committed person may petition for discharge with the approval of the secretary of the department, Wis. Stat. § 980.09(1), or without the secretary's approval, Wis. Stat. § 980.09(2). There is also an additional discharge procedure that can be invoked by the committed person at any time, although this option carries some procedural obstacles if prior discharge petitions have been denied or declared frivolous. See Wis. Stat. § 980.10 (If there are prior denials or frivolous petitions, "the court shall deny any subsequent petition under this section without a hearing unless the petition contains facts upon which a court could find that the condition of the person had so changed that a hearing was warranted."). As-*729snrm'ng no previous denials or frivolous petitions, a petition for discharge pursuant to Wis. Stat. § 980.10 triggers the procedures in Wis. Stat. § 980.09. At the hearing on any of these discharge petitions, "[t]he state has the burden of proving by clear and convincing evidence that the petitioner is still a sexually violent person." Wis. Stat. § 980.09(l)(b) and (2)(b).
¶ 14. We have held that Chapter 980 "is aimed primarily at treating the sexually violent person, not punishing the individual." State v. Carpenter, 197 Wis. 2d 252, 267, 541 N.W.2d 105 (1995). The law is intended to "protects the public by providing concentrated treatment for convicted sex offenders who are at a high risk to reoffend based upon a mental disorder which predisposes them to commit acts of sexual violence." Id. at 273-74. Protection of the public and treatment of persons who are dangerous because of mental disorders that predispose them to sexual violence are "significant nonpunitive and remedial purposes" that justify indefinite civil commitment. Id. at 271; State v. Post, 197 Wis. 2d 279, 314, 541 N.W.2d 115 (1995). Chapter 980 provides for discharge from commitment once the statutorily-defined dangerousness "abates." Carpenter, 197 Wis. 2d at 268 (citing Wis. Stat. § 980.09). Until that point, "[c]ommitment in a secure setting that provides specialized treatment for sexual offenders serves both to protect society and to treat the individual." Post, 197 Wis. 2d at 314.
A. Mandatory Or Directory
¶ 15. We agree with the court of appeals that the time limits for periodic reexamination contained in Wis. *730Stat. § 980.07(1) are mandatory rather than directory.6 See Marberry, 254 Wis. 2d 690, ¶ 27. Whether a statutory provision is mandatory or directory is a question of legislative intent. R.R.E., 162 Wis. 2d at 707. "Although the use of the word 'shall' in a statute suggests that the provision is mandatory, this court has often held that statutory time limits are directory despite the use of the word 'shall.'" Id. Thus, "the determination of whether 'shall' is mandatory or directory is not governed by a per se rule." Id.
¶ 16. Although we have stated that there is no per se rule, we have also held that "[t]he general rule in interpreting statutory language is that the word 'shall' is presumed mandatory. Further support is given to a mandatory interpretation of 'shall' when the legislature uses the words 'shall' and 'may' in a particular statutory section, indicating the legislature was aware of the distinct meanings of the words." In re Commitment of Sprosty, 227 Wis. 2d 316, 324, 595 N.W.2d 692 (1999)(ci-tations and internal quotation marks omitted). The legislature has used both the word "shall" and the word "may" in Wis. Stat. § 980.07.7 "Therefore, we 'can infer that the legislature was aware of the different denotations and intended the words to have their precise meanings.'" Id. at 325 (quoting Karow v. Milwaukee County Civ. Serv. Comm'n, 82 Wis. 2d 565, 571, 263 N.W.2d 214 (1978)).
¶ 17. In addition to the foregoing general rules, we consider the following factors in determining *731whether a statutory time limit is mandatory or directory: "the existence of penalties for failure to comply with the limitation, the statute's nature, the legislative objective for the statute, and the potential consequences to the parties, such as injuries or wrongs." State v. Thomas, 2000 WI App 162, ¶ 9, 238 Wis. 2d 216, 222, 617 N.W.2d 230; see also R.R.E., 162 Wis. 2d at 708.
¶ 18. The statute does not provide a penalty for failure to comply with the time limits for periodic reexamination. While "[t]he legislature's failure to state the consequences of noncompliance with the established time limit lends support for construing the statute as directory," the absence of a penalty for noncompliance "is only one factor to be considered in the analysis of whether the legislature intended the provision to be mandatory or directory." Karow, 82 Wis. 2d at 571-72.
¶ 19. As we have noted, Chapter 980 is a civil commitment statute with dual objectives: protection of the public and treatment of persons with dangerous mental disorders. Untimely periodic reexamination frustrates the treatment objective and may keep persons who are no longer a danger to the public in institutionalized care longer than necessary.
¶ 20. In this regard, the failure to comply with the time limits for periodic reexamination has substantial consequences for the committed person. The initial and periodic reexaminations determine the committed person's appropriateness for continued institutional care, supervised release, or discharge. As the court of appeals observed, the "committed person's liberty hinges upon this initial reexamination." Marberry, 254 Wis. 2d 690, ¶ 27.
*732¶ 21. The weight of these considerations leads us to conclude, as did the court of appeals, that the time limits for periodic reexamination in Wis. Stat. § 980.07(1) are mandatory. This conclusion, however, does not necessarily require release and discharge from commitment as a remedy for noncompliance with the statutory mandate.
B. Remedy
¶ 22. "The writ of habeas corpus has its origins in the common law, and its availability is guaranteed by the U.S. Constitution, the Wisconsin Constitution, and by state and federal statute."8 Haas, 252 Wis. 2d 133, ¶ 11 (citing State ex rel. Fuentes v. Court of Appeals, 225 Wis. 2d 446, 450, 593 N.W.2d 48 (1999)); see also U.S. Const. art. I, § 9, cl. 2; 28 U.S.C. § 2241; Wis. Const. art I, § 8(4); Wis. Stat. § 782.01. Habeas corpus is a civil proceeding which "test[s] the right of a person to his personal liberty." State ex rel. Dowe v. Waukesha County Cir. Ct., 184 Wis. 2d 724, 728, 516 N.W.2d 714 (1994). The purpose of the writ is to protect and vindicate the petitioner's right to be free from illegal restraint. State ex rel. Zdanczewicz v. Snyder, 131 Wis. 2d 147, 151, 388 N.W.2d 612 (1986).
¶ 23. The extraordinary relief provided by the writ of habeas corpus is available only in limited circumstances and is subject to three prerequisites. Haas, *733252 Wis. 2d 133, ¶ 12. First, the petitioner must be restrained of his liberty. Id. Second, the restraint must have been imposed without jurisdiction or contrary to constitutional protections. Id. Third, the petitioner must demonstrate that there are no other adequate remedies available in the law. Id. Absent a showing that all three criteria are met, the writ of habeas corpus will not issue. Id.
¶ 24. In Haas, we evaluated the propriety of ha-beas relief by reference to the third requirement alone, because our conclusion on the adequacy of alternative remedies was dispositive. Id., ¶ 13. We do the same here. While there is no dispute that Marberry is restrained of his liberty, the parties disagree about whether the department's noncompliance with the statutorily mandated time limits for initial reexamination affects the constitutionality of the underlying commitment or the competency of the court to conduct further proceedings in connection with the commitment. The court of appeals did not directly address this second criterion for habeas relief. In any event, because the absence of any of the three habeas requirements defeats the writ, we confine our analysis to the third requirement, as we did in Haas.
¶ 25. "The writ of habeas corpus does not issue as a right." Id., ¶ 14.
We have long and consistently held that the extraordinary writ of habeas corpus is not available to a petitioner when the petitioner has other adequate remedies available. For instance, habeas corpus is not available to challenge a bindover decision by a court commissioner because the decision is challengeable on a statutory motion to dismiss. Similarly, the writ is not available to challenge the sufficiency of probable cause to issue a criminal complaint, even when the challenge is *734brought between arrest and the preliminary hearing, because the challenge can be made using other remedies at trial. Habeas corpus proceedings are likewise not available to challenge an administrative order revoking probation, since a writ of certiorari is available, and is the proper remedy under such circumstances. In short, if the petitioner has an otherwise adequate remedy that he or she may exercise to obtain the same relief, the writ will not be issued.
Id. (citations omitted).
¶ 26. It is undeniably true that in Marberry's case, the department was in prolonged and inexcusable noncompliance with its mandatory duties under Wis. Stat. § 980.07. Nevertheless, the law provides adequate remedies for the failure to conduct timely periodic reexaminations other than release pursuant to a habeas writ. Chapter 980 contains a procedure, outlined above, by which a committed person can trigger a court-ordered reexamination via a petition for supervised release pursuant to Wis. Stat. § 980.08.
¶ 27. As we have noted, Wis. Stat. § 980.08 was amended in 1999 to preclude petitions for supervised release during the first 18 months of commitment.9 Under certain circumstances, therefore, this statutory vehicle for compelling reexamination may be unavailable. There is, in such circumstances, another remedy: a writ of mandamus to compel an initial or periodic reexamination, backed up by contempt, with a fine or jail as a sanction. Mandamus may issue to compel a *735public officer to perform a duty of his office presently due to be performed where there is a clear legal right, a positive and plain duty, substantial damage in the absence of performance, and no other adequate remedy. Pasko v. City of Milwaukee, 2002 WI 33, ¶ 24, 252 Wis. 2d 1, 643 N.W.2d 72. Because Wis. Stat. § 980.07 imposes a mandatory duty upon the department, mandamus to compel performance of that duty is an appropriate and available remedy.
¶ 28. As Judge Brown noted in his partial dissent in this case, "[w]here a writ [of mandamus] or court order has been issued and the mental reexamination still has not been performed, as is the case in this instance, the public officials may be held in contempt for their failure to comply with the order. .. . [T]his remedy would be an effective tool precisely because it focuses on the particular persons who have the authority to ensure that procedures are established to carry out the requirements of the statute." Marberry, 254 Wis. 2d 690, ¶ 52 (Brown, J., concurring in part, dissenting in part).
¶ 29. We agree with Judge Brown on the adequacy and appropriateness of mandamus and contempt as remedies for the department's failure to perform its mandatory duties under Wis. Stat. § 980.07. Release and discharge from commitment pursuant to habeas for failure to conduct a timely reexamination would jeopardize public safety and contradict the express statutory criteria for supervised release and discharge. Chapter 980 provides that a person committed may be released on supervision or discharged from commitment only after a court finds that he or she is no longer a sexually violent person and that it is no longer substantially probable that he or she will commit acts of sexual violence. See Wis. Stat. §§ 980.08, 980.09, *736980.10; see also Wis. Stat. § 980.06 (Sexually violent persons are committed to the department for "control, care and treatment until such time as the person is no longer a sexually violent person."). Release absent this substantive determination by a court would compromise both of Chapter 980's principal purposes— treatment and public protection — because, until a circuit court finds otherwise, the committed person remains in need of treatment and at high risk to reoffend.
¶ 30. "Release of a ch. 980 patient whose dangerousness or mental disorder has not abated serves neither to protect the public nor provide care and treatment for the patient." Marberry, 254 Wis. 2d 690, ¶ 39 (Brown, J., concurring in part, dissenting in part.) Accordingly, "release is not only inappropriate, it is not justifiable under the dual purposes of the statute: protection of the public from sexually violent persons likely to reoffend and care and treatment of the patient." Id., ¶ 42. Mandamus and contempt are more appropriate to the purposes of the statute:
If the purpose is to provide a sanction that will force state officials to follow the law, contempt is the better sanction than release [of the committed person]. Release is an excessive sanction because the costs are way too high. Contempt is workable and gets the message out to the people who are really and finally responsible for violating the legislature's mandatory time periods for reexamination. The cost is visited upon these flagrant violators and not the public. If someone at [the department] knew he or she could go to jail for ignoring a mandamus, he or she would take extra care to make sure the individual received his or her reexamination.
Id., ¶ 54.
*737¶ 31. Although admittedly in a somewhat different context, we have previously held that the failure to comply with reexamination time limits in a civil commitment does not necessarily require release as a remedy. R.R.E., 162 Wis. 2d at 711-12.10 R.R.E. involved a Chapter 51 commitment following a verdict of not guilty by reason of mental disease or defect in a criminal case pursuant to Wis. Stat. § 971.17. R.R.E., 162 Wis. 2d at 703. The circuit court failed to conduct a hearing within 30 days of the filing of a reexamination petition as required by Wis. Stat. § 51.20(16)(e). In R.R.E., we recognized the "strong competing policy of requiring courts to strictly follow procedural rules and time limitations which are designed to ensure that the *738right of committed persons to a hearing to review the need for their continued confinement is not unduly delayed or effectively denied by a court's delays." Id. at 711.
¶ 32. We concluded, however, that had the legislature intended to provide for release when the time limits for the reexamination hearing were violated, it likely "would have expressly stated its intention in order to alert the circuit courts of the extreme consequences for failing to comply with the time limitations." Id. at 710. We further held that the statutory policy of protecting the public outweighed the competing interest of the committed individual in receiving his or her hearing in. strict accordance with the statutory time limitations for the reexamination hearing. Id. at 711. Although these conclusions were reached in the context of a decision that the statutory time limits were directory rather than mandatory (unlike our conclusion here), we also observed that release was not proper as a matter of remedy, because the committed individual retained the ability to compel a hearing through other statutory means, and also by a writ of mandamus, when the time limitation in the statute went unobserved. Id. at 714-15.
¶ 33. Similarly here, release is not the only adequate remedy for noncompliance with the statutory time limits for reexamination, because the committed person retains the ability to compel a reexamination under the statutory procedure for supervised release, or, if the statutory remedy is unavailable, by a writ of mandamus. These remedies are effective and adequate, and consistent with statutory purposes of treatment and protection of the public.
*739¶ 34. For the foregoing reasons, therefore, we conclude that Marberry is not entitled to release from his Chapter 980 commitment as a remedy for the department's failure to perform an initial reexamination in accordance with the six-month time limit of Wis. Stat. 980.07(1).11 Because there are adequate, alternative remedies available, relief pursuant to habeas corpus is improper.
By the Court. — The decision of the court of appeals is reversed.
¶ 35. JUSTICE DAVID T. PROSSER, JR. did not participate.All subsequent statutory references are to the 2001-2002 version of the statutes.
We take judicial notice of the subsequent reexamination proceeding. We also take judicial notice that Marberry has received a third reexamination, subsequent to oral argument in this case. At a hearing in Dane County Circuit Court on December 12, 2002, the Honorable Daniel R. Moeser held that Marberry remains a sexually violent person and ordered that his commitment continue.
The chapter's provisions have been upheld against repeated challenge. See, e.g., In re Commitment of Laxton, 2002 WI 82, 254 Wis. 2d 185, 647 N.W.2d 784, cert. denied, 123 S.Ct. 870 (2003); In re Commitment of Curiel, 227 Wis. 2d 389, 597 N.W.2d 697 (1999); In re Commitment of Kienitz, 227 Wis. 2d 423, 597 N.W.2d 712 (1999); State v. Post, 197 Wis. 2d 279, 541 *727N.W.2d 115 (1995), cert. denied 521 U.S. 1118 (1997); State v. Carpenter, 197 Wis. 2d 252, 541 N.W.2d 105 (1995), cert. denied, 521 U.S. 1118 (1997).
Indigent persons have the right to a court-appointed examining expert. See Wis. Stat. § 980.03(4). ("If the person is indigent, the court shall, upon the person's request, appoint a qualified and available expert or professional person to perform an examination and participate in the trial or other proceeding on the person's behalf.").
At the time Marberry was committed in 1998, this statute allowed a petition for supervised release after only six months. The six-month period was amended to 18 months by 1999 Wis. Act 9, § 3232p, effective October 29, 1999.
The department did not contest this conclusion in its current briefs, and conceded this point at oral argument. Accordingly, we address it only briefly.
See Wis. Stat. 980.07(1) ("the department shall conduct an examination") and Wis. Stat. § 980.07(3) ("the court... may order a reexamination") (emphasis added).
Literally, habeas corpus is an imperative that translates to "that you have the body." A writ of habeas corpus is used to command an official "to bring a person before a court, most frequently to ensure that the party's imprisonment or detention is not illegal." See Black's Law Dictionary 715 (7th ed. 1999).
See supra note 5. As we have also noted, however, at the time Marberry was committed in 1998, the statute allowed him to file a petition for supervised release after only six months, the same timeframe as the initial reexamination under Wis. Stat. § 980.07(1).
As a general matter, Chapter 51 commitments are permitted for reasons other than danger to others, although R.R.E. arose in the context of a Chapter 51 commitment following a verdict of not guilty by reason of mental disease or defect in a criminal case pursuant to Wis. Stat. § 971.17. State v. R.R.E., 162 Wis. 2d 698, 703, 470 N.W.2d 283 (1991). In contrast, under Chapter 980, significant danger to others is the only justification for commitment. Persons committed under Chapter 980, therefore, are considered more dangerous as a class than those committed under Chapter 51. See Post, 197 Wis. 2d at 322. This distinction between Chapter 980 and other types of civil commitment led the court of appeals to distinguish this case from State ex rel. Lockman v. Gerhardstein, 107 Wis. 2d 325, 320 N.W.2d 27 (Ct. App. 1982) (failure to conduct final commitment hearing within 14 days of detention pursuant to Wis. Stat. § 51.20(7)(c) requires release from temporary detention and dismissal of commitment petition); and N.N. v. County of Dane, 140 Wis. 2d 64, 409 N.W.2d 388 (Ct. App. 1987) (same result in Chapter 55 protective placement). Marberry, 254 Wis. 2d 690, ¶¶ 6-16. We agree with the court of appeals' analysis on this point. Lockman and N.N. were also in a different procedural posture than this case, as commitment had not yet occurred in either case.
We emphasize again that Marberry has now been reexamined, three times, and his mental disorder and dangerousness has not abated. According to each of these reexaminations, he remains a sexually violent person.