The petitioner, Trevelle Dinham, appeals from the judgment of the habeas court dismissing his petition for a writ of habeas corpus. On appeal, the petitioner argues that the court improperly dismissed his claims for lack of subject matter jurisdiction and for the failure to state a claim upon which habeas relief can be granted. Specifically, the petitioner argues that the court improperly dismissed his claims that (1) he relied on "governmental representations" that he would receive risk reduction credit when he pleaded guilty to manslaughter in the first degree with a firearm, (2) the respondent, the Commissioner of Correction, misconstrued and misapplied several statutes pertaining to the petitioner receiving a parole suitability hearing, earning risk reduction credit in the future, and applying risk reduction credit toward the advancement of the petitioner's parole eligibility date, and (3) the respondent's customary practices have created a vested liberty interest in receiving a parole suitability hearing, earning future risk reduction credits, and applying risk reduction credits to advance his parole eligibility date. We disagree and, accordingly, affirm the judgment of the habeas court.

The following facts and procedural history are relevant to the resolution of this appeal. On April 2, 2012, the petitioner pleaded guilty to one count of manslaughter in the first degree with a firearm in violation of General Statutes § 53a-55a, which he committed on or about September 24, 1999, 1 and for which he was sentenced to twenty-eight years of imprisonment. Thereafter, the then self-represented petitioner commenced this action by filing a petition for a writ of habeas corpus. On November 15, 2017, the petitioner, after obtaining counsel, filed an eighteen count amended habeas petition. On March 19, 2018, the court, sua sponte, dismissed the amended petition for lack of subject matter jurisdiction and for the failure to state a claim upon which habeas relief may be granted. 2 See Practice Book § 23-29. 3 Instead of addressing the petitioner's claims individually, the court broadly determined that it lacked subject matter jurisdiction over the habeas petition and that the petition had failed to state a claim upon which habeas relief can be granted. 4 The court granted the petitioner's petition for certification to appeal. 5 The petitioner timely filed the present appeal, challenging the dismissal of ten of his claims. Additional facts will be set forth as necessary.

Before addressing the petitioner's individual claims, we first set forth the standards of review and relevant legal principles applicable to the petitioner's appeal. "Subject matter jurisdiction involves the authority of the court to adjudicate the type of controversy presented by the action before it .... [A] court lacks discretion to consider the merits of a case over which it is without jurisdiction .... The subject matter jurisdiction requirement may not be waived by any party, and also may be raised by a party, or by the court sua sponte, at any stage of the proceedings, including on appeal." (Internal quotation marks omitted.) Pentland v. Commissioner of Correction , 176 Conn. App. 779 , 784-85, 169 A.3d 851 , cert. denied, 327 Conn. 978 , 174 A.3d 800 (2017). "[I]n order to invoke successfully the jurisdiction of the habeas court, a petitioner must allege an interest sufficient to give rise to habeas relief .... We have long held that because [a] determination regarding a trial court's subject matter jurisdiction is a question of law, our review is plenary." (Citation omitted; internal quotation marks omitted.) Perez v. Commissioner of Correction , 326 Conn. 357 , 368, 163 A.3d 597 (2017). "With respect to the habeas court's jurisdiction, [t]he scope of relief available through a petition for habeas corpus is limited. In order to invoke the trial court's subject matter jurisdiction in a habeas action, a petitioner must allege that he is illegally confined or has been deprived of his liberty .... In other words, a petitioner must allege an interest sufficient to give rise to habeas relief .... In order to ... qualify as a constitutionally protected liberty [interest] ... the interest must be one that is assured either by statute, judicial decree, or regulation." (Internal quotation marks omitted.) Boria v. Commissioner of Correction , 186 Conn. App. 332 , 342, 199 A.3d 1127 (2018).

"Likewise, [w]hether a habeas court properly dismissed a petition pursuant to Practice Book § 23-29 (2), on the ground that it fails to state a claim upon which habeas corpus relief can be granted, presents a question of law over which our review is plenary." (Internal quotation marks omitted.) Perez v. Commissioner of Correction , supra, 326 Conn. at 368 , 163 A.3d 597 . "In reviewing whether a petition states a claim for habeas relief, we accept its allegations as true." Coleman v. Commissioner of Correction , 137 Conn. App. 51 , 55, 46 A.3d 1050 (2012). For ease of discussion, we next provide a brief summary of the relevant laws pertaining to the petitioner's ability to receive a parole suitability hearing, to earn future risk reduction credit, and to apply his earned risk reduction credit toward the advancement of his parole eligibility date.

Pursuant to No. 04-234 of the 2004 Public Acts, codified at General Statutes § 54-125a (e), the Board of Pardons and Paroles (board) was required to hold a parole suitability hearing for any person eligible for parole who had completed 85 percent of his or her sentence. General Statutes (Rev. to 2013) § 54-125a (e) subsequently was amended by No. 13-247 of the 2013 Public Acts (P.A. 13-247), to make the board's parole suitability hearing discretionary, rather than mandatory. 6 If the board declines to hold a hearing, however, § 54-125a (e) requires the board to document specific reasons for declining to hold a hearing and to provide those reasons to the person denied a hearing.

As to risk reduction credits, our Supreme Court has summarized the relevant statutes as follows: "In July, 2011 ... General Statutes § 18-98e 7 became effective, pursuant to which the respondent had discretion to award risk reduction credit toward a reduction of an inmate's sentence, up to five days per month, for positive conduct. General Statutes § 18-98e (a) and (b). The respondent also was vested with discretion to revoke such credit, even credit yet to be earned, for good cause. See General Statutes § 18-98e (b). At the same time, the legislature amended the parole eligibility provision to provide: 'A person convicted of ... an offense ... where the underlying facts and circumstances of the offense involve the use, attempted use or threatened use of physical force against another person shall be ineligible for parole under subsection (a) of this section until such person has served not less than eighty-five per cent of the definite sentence imposed less any risk reduction credit earned under the provisions of section 18-98e .' ... General Statutes (Rev. to 2011) § 54-125a (b) (2), as amended by Public Acts 2011, No. 11-51, § 25 (P.A. 11-51). The subsection of § 54-125a addressing parole hearings was similarly amended to account for earned risk reduction credit. General Statutes (Rev. to 2011) § 54-125a (e), as amended by P.A. 11-51, § 25. Accordingly, under the 2011 amendments, earned risk reduction credit was to be applied to an inmate's definite sentence to advance the inmate's end of sentence date, and the parole eligibility date calculated as a percentage of the sentence would advance in similar measure ....

"Under the 2011 amendments to § 54-125a and § 18-98e, any risk reduction credit earned by an inmate, and not subsequently revoked, would have both reduced his sentence and rendered him eligible for a hearing to determine whether he should be granted parole after he had served 85 percent of that reduced sentence.

"Effective July 1, 2013, the legislature again amended § 54-125a. Specifically, with regard to offenses like one of those of which the petitioner was convicted, the legislature eliminated the language that permitted the parole eligibility date to be advanced by the application of any earned risk reduction credit. See [Public Acts 2013, No. 13-3, § 59 (P.A. 13-3) ]." (Emphasis in original; footnote altered.) Perez v. Commissioner of Correction , supra, 326 Conn. at 363-65 , 163 A.3d 597 .

General Statutes (Rev. to 2015) § 18-98e (a) subsequently was amended by No. 15-216 of the 2015 Public Acts (P.A. 15-216), 8 so that inmates convicted of certain violent crimes, including manslaughter in the first degree with a firearm, were ineligible to earn risk reduction credits in the future. 9 Mindful of the foregoing legal principles, we now turn to the specific claims raised by the petitioner in this appeal.

I

The petitioner's first argument is that the court improperly dismissed his claims that, when he pleaded guilty in 2012 to manslaughter in the first degree with a firearm, he relied on "governmental representations" 10 that he would receive risk reduction credits to advance his parole eligibility date and reduce the total length of his sentence. 11 Specifically, the petitioner claims in his appellate brief that he pleaded guilty to manslaughter in the first degree with a firearm, which carried a twenty-eight year term of imprisonment, rather than murder, which carried a twenty-five year term of imprisonment, because either the court or the prosecutor represented that, if he pleaded guilty to the manslaughter charge, he would be eligible to earn risk reduction credits that would advance his parole eligibility date and would reduce the total length of his sentence to under twenty-five years. The petitioner, relying on Santobello v. New York , 404 U.S. 257 , 92 S. Ct. 495 , 30 L. Ed. 2d 427 (1971), 12 argues that his operative petition states a cognizable liberty interest by virtue of his "right to rely on governmental representations," which confers subject matter jurisdiction on the court. Moreover, he asserts that the facts pleaded in his petition state a claim upon which habeas relief can be granted. We disagree. The petitioner failed to plead in his amended petition any factual basis upon which his claim relies. The petitioner only broadly alleged, citing to Santobello , that he has a liberty interest in "being able to rely on governmental representations in the decision how to resolve his pending case," without any factual allegations of what the representations were or who made them. "It is well settled that [t]he petition for a writ of habeas corpus is essentially a pleading and, as such, it should conform generally to a complaint in a civil action .... The principle that a plaintiff may rely only upon what he has alleged is basic." (Internal quotation marks omitted.) Arriaga v. Commissioner of Correction , 120 Conn. App. 258 , 262, 990 A.2d 910 (2010), appeal dismissed, 303 Conn. 698 , 36 A.3d 224 (2012). "[A] habeas petitioner is limited to the allegations in his petition, which are intended to put the [respondent] on notice of the claims made, to limit the issues to be decided, and to prevent surprise." (Internal quotation marks omitted.) Moye v. Commissioner of Correction , 316 Conn. 779 , 789, 114 A.3d 925 (2015). Accordingly, we conclude that the court did not err in dismissing the petitioner's claims for failure to state a claim upon which habeas relief can be granted. 13

II

The petitioner next argues that the court improperly dismissed several counts of his operative habeas petition, which allege that three public acts amending §§ 54-125a or 18-98e are substantive rather than procedural in nature and, therefore, should not apply retroactively to him. 14 Specifically, the petitioner claims that the respondent has misinterpreted and misapplied (1) P.A. 13-247, which amended General Statutes (Rev. to 2013) § 54-125a (e) to make a parole suitability hearing discretionary rather than mandatory, (2) P.A. 13-3, which amended General Statutes (Rev. to 2013) § 54-125a to eliminate the use of risk reduction credits to advance the parole eligibility date of inmates convicted of certain crimes, including manslaughter in the first degree with a firearm, and (3) P.A. 15-216, which amended General Statutes (Rev. to 2015) § 18-98e to prohibit inmates who committed certain crimes, including first degree manslaughter with a firearm, from earning any further risk reduction credit. We disagree.

As to the petitioner's claim regarding P.A. 13-247, even though it is unclear on what basis the court relied in concluding that it lacked subject matter jurisdiction and that the petition had failed to state a claim upon which habeas relief could be granted, our plenary review leads us to conclude that, as argued by the respondent in his principal brief, there is another basis for finding a lack of subject matter jurisdiction, namely, that the petitioner's claim is not ripe for adjudication. "The subject matter jurisdiction requirement may not be waived by any party, and also may be raised by a party, or by the court sua sponte, at any stage of the proceedings, including on appeal." (Internal quotation marks omitted.) Pentland v. Commissioner of Correction , supra, 176 Conn. App. at 785 , 169 A.3d 851 . "[A] trial court must be satisfied that the case before [it] does not present a hypothetical injury or a claim contingent [on] some event that has not and indeed may never transpire .... [R]ipeness is a sine qua non of justiciability ...." (Internal quotation marks omitted.) Perez v. Commissioner of Correction , supra, 326 Conn. at 387-88 , 163 A.3d 597 . In Perez , our Supreme Court stated that, even if the petitioner in that case had stated a statutory claim upon which habeas relief could be granted, his challenge to P.A. 13-247 would not be ripe for adjudication because it was impossible to determine whether the board would decline to conduct a hearing on the petitioner's parole eligibility date. 15 Id. In the present case, the petitioner also has not yet been denied a hearing, and it is impossible to determine whether a hearing will take place in the future. 16 Accordingly, the petitioner's claim related to P.A. 13-247 is not ripe for review.

Turning to P.A. 13-3 and P.A. 15-216, in his appellate brief, the petitioner cites to Johnson v. Commissioner of Correction , 258 Conn. 804 , 786 A.2d 1091 (2002), for the proposition that this court must hold that the public acts relevant to his claim are substantive in nature and, therefore, cannot be applied retroactively to him. 17 In Johnson , our Supreme Court determined that the petitioner had made a cognizable ex post facto claim , which invoked the habeas court's subject matter jurisdiction. Id., at 818-19, 786 A.2d 1091 . An ex post facto claim, however, is not dependent on the existence of a cognizable liberty interest. See Breton v. Commissioner of Correction , 330 Conn. 462 , 471, 196 A.3d 789 (2018) ("[t]he presence or absence of an affirmative, enforceable right is not relevant ... to the ex post facto prohibition, which forbids the imposition of punishment more severe than the punishment assigned by law when the act to be punished occurred" [internal quotation marks omitted] ); see also Baker v. Commissioner of Correction , 281 Conn. 241 , 261, 914 A.2d 1034 (2007).

In the present case, the petitioner has stated that his claim is not an ex post facto claim but, rather, a statutory interpretation claim. Accordingly, Johnson is materially distinguishable from the present case. Citing to Perez v. Commissioner of Correction , supra, 326 Conn. at 387-88 , 163 A.3d 597 , the petitioner asserts that his claim is not controlled by the question of whether he has alleged a cognizable liberty interest in receiving risk reduction credit. In essence, the petitioner asks for this court to reach the merits of his claim without him first alleging a cognizable liberty interest sufficient to establish a basis for the court's subject matter jurisdiction. Such a reading of Perez would run contrary to our jurisprudence, which has consistently held that "[i]n order to invoke the trial court's subject matter jurisdiction in a habeas action, a petitioner must allege that he is illegally confined or has been deprived of his liberty." (Internal quotation marks omitted.) Boria v. Commissioner of Correction , supra, 186 Conn. App. at 342 , 199 A.3d 1127 . Accordingly, the petitioner must assert a cognizable liberty interest sufficient to invoke the habeas court's subject matter jurisdiction.

"Our appellate courts have concluded, consistently, that an inmate does not have a constitutionally protected liberty interest in certain benefits-such as good time credits, risk reduction credits, and early parole consideration-if the statutory scheme pursuant to which the [respondent] is authorized to award those benefits is discretionary in nature." Green v. Commissioner of Correction , 184 Conn. App. 76 , 86-87, 194 A.3d 857 , cert. denied, 330 Conn. 933 , 195 A.3d 383 (2018) ; see Perez v. Commissioner of Correction , supra, 326 Conn. at 370-73 , 163 A.3d 597 (no liberty interest in risk reduction credits or application of risk reduction credits to advance parole eligibility date); see also Rivera v. Commissioner of Correction , 186 Conn. App. 506 , 514, 200 A.3d 701 (2018), cert. denied, 331 Conn. 901 , 201 A.3d 402 (2019), and cases cited therein. Because the petitioner has failed to assert a cognizable liberty interest in his claims, we conclude that the court lacked subject matter jurisdiction over them.

III

Finally, the petitioner claims that the court improperly dismissed five counts in his petition for lack of subject matter jurisdiction and for the failure to state a claim upon which habeas relief can be granted because his claims established a cognizable liberty interest by alleging that the respondent, through his customary practices, has created a liberty interest. 18 We are not persuaded.

As previously mentioned, our Supreme Court has held that, "[i]n order to ... qualify as a constitutionally protected liberty [interest] ... the interest must be one that is assured either by statute, judicial decree, or regulation." (Internal quotation marks omitted.)

Boria v. Commissioner of Correction , supra, 186 Conn. App. at 342, 199 A.3d 1127 . There is no liberty interest in earning risk reduction credit or having it applied to further an inmate's parole eligibility date due to the discretionary nature of the respective statutory schemes. See part II of this opinion. Furthermore, there is no liberty interest in parole or the procedure by which parole is granted or denied. See Perez v. Commissioner of Correction , supra, 326 Conn. at 373 , 163 A.3d 597 ("[w]here ... an inmate has no vested liberty interest in parole itself, then it follows that the procedure by which the board exercises its discretion to award or deny the petitioner parole does not implicate a vested liberty interest"). Thus, it would be contrary to our case law to hold in the present case that the petitioner has a vested liberty interest in earning future risk reduction credits, in having those credits utilized to advance his parole eligibility date, and in having a mandatory parole suitability hearing, all of which are not assured either by statute, judicial decree, or regulation.

The petitioner primarily relies on two federal cases to support the proposition that the respondent's customary practices created a cognizable liberty interest sufficient to confer subject matter jurisdiction over his petition. First, he cites to Vitek v. Jones , 445 U.S. 480 , 487-88, 100 S. Ct. 1254 , 63 L. Ed. 2d 552 (1980), in which the United States Supreme Court held that an inmate had a cognizable liberty interest in not being transferred to a mental health facility for treatment. Specifically, the court found that such a liberty interest was created from an expectation based on Nebraska statutes and the prison's practice that an inmate would not be transferred unless he suffered from a mental disease or defect that could not be treated at the prison. Id., at 489-90 , 100 S. Ct. 1254 . Importantly, the court also factored into its conclusion the stigma created by an involuntary confinement to a mental health institution, which it opined could negatively impact the inmate. Id., at 492 , 100 S. Ct. 1254 .

Second, the petitioner cites to Arsberry v. Sielaff , 586 F.2d 37 , 47 (7th Cir. 1978), in which the plaintiffs claimed that, on the basis of prison policy and customs, they were entitled to earn good time credit during their segregation from the general prison population. The court acknowledged that, absent a liberty interest protected by the United States constitution, it must look primarily to state law to determine if a liberty interest was created. Id., at 45-46 . In addition to state statutes and prison administrative regulations, the court determined that a liberty interest may also be found in official policies or practices if a prisoner could show "some restriction upon the prison officials' discretion to remove the benefit sought." Id., at 46-48 . In light of new evidence that four prison directives provided guidelines for denying good time credit in the event a prisoner was segregated from the general prison population, the court remanded the case to the trial court for an evidentiary hearing as to whether the directives created a state law entitlement. Id., at 47 .

A key distinction between the cases relied on by the petitioner and the present case is that, when looking to our state law, the legislature has barred the respondent from awarding further risk reduction credits to the petitioner or from applying the credits the petitioner has earned to advance his parole eligibility date. Indeed, the legislature has made it clear in its amendments to §§ 54-125a and 18-98e that the respondent is no longer authorized to utilize risk reduction credits to advance an inmate's parole eligibility date and that he may no longer issue risk reduction credits to inmates such as the petitioner. In other words, if we were to hold in this case that a liberty interest has been created in the earning of future risk reduction credit, the application of risk reduction credit to advance the petitioner's parole eligibility date, and in receiving a parole suitability hearing, we would usurp the power vested in the legislature, which broadly dictates to the respondent, a member of the executive branch, how to administer and apply risk reduction credit and conduct parole suitability hearings. "Because the ultimate power rests in the people and has been allocated to the separate branches of government, it is our duty to ensure that each branch, including the judiciary, does not usurp the power of its coequal branches. It is especially important that we take pains to restrain this branch , because a usurpation of legislative or executive power is, in effect, a usurpation of the people's power." (Emphasis in original.) State v. Peeler , 321 Conn. 375 , 464, 140 A.3d 811 (2016) ( Zarella , J. , dissenting). Therefore, we decline to interfere with the legislature's clear mandate. Accordingly, the court properly dismissed the petitioner's operative habeas petition for lack of subject matter jurisdiction and for the failure to state a claim upon which habeas corpus relief can be granted.

The judgment is affirmed.

In this opinion the other judges concurred.