The Fifth Amendment to the United States Constitution provides, “No person ... shall be compelled in any criminal case to be a witness against himself.” According to section 903A.2(l)(a) (2007) of the Iowa Code, an incarcerated sex offender is not eligible for an earned-time reduction of sentence unless that person completes a sex offender treatment program. The question presented here is whether section 903A.2(l)(u) violates the Fifth Amendment rights of a convicted sex offender, when successful completion of the treatment program would require him to acknowledge responsibility for his offense.
We conclude there is no Fifth Amendment violation. For the reasons discussed herein, we believe the State of Iowa may use earned-time credits as an incentive for convicted sex offenders to obtain sex offender treatment, even when the treatment requires an acknowledgment of responsibility.
I. Background Facts and Proceedings.
On March 21, 2006, Robert Harkins was convicted of third-degree sexual abuse following a jury trial. The court of appeals, in upholding Harkins’s conviction on direct appeal, summarized the relevant facts as follows:
On August 27, 2005, Robert Harkins went out drinking with some friends. The group ended up at the home of [the victim]. After a short period of time most of the group left, except for Derrick, Trisha, Harkins, and [the victim]. Derrick, who was [the victim’s] former boyfriend, passed out on the couch. Trisha went to sleep in one of the bedrooms. Harkins laid down in [the victim’s] bedroom in all of his clothes. [The victim] stated she believed Harkins was sleeping or passed out, so she laid down to sleep on the other side of the bed.
[The victim] testified Harkins rolled over on top of her, and she told him to get off. Harkins pinned [the victim] down and pulled her clothing off. [The victim] testified she repeatedly told Har-kins no, stating, “I told him no. I told him to stop.” Harkins proceeded to engage in sexual intercourse with her. When Harkins stopped she kneed him and pushed him off, then screamed at him that she had said no. Trisha heard [the victim] say, “No, I said no.” Trisha went to investigate, and met [the victim] coming out of her bedroom, clad only in a blanket and crying hysterically. Trisha stated she saw blood on [the victim’s] bed. Harkins then left the home.
*516Trisha and [the victim] called the police, and deputy sheriff Kevin Knoche responded to the call. Deputy Knoche also saw blood on [the victim’s] bed. Deputy Knoche found Harkins sleeping at the home of a friend. Harkins was not wearing his underwear, but it was stuck in the fly of his pants. Harkins denied having sex with [the victim] and stated he could not recall anything like that occurring.
[The victim] was taken to a hospital for a physical examination. [The victim] had three tears, which were bleeding, in the area of the perineum. Nancy Downing, a registered nurse, testified she did not usually find tears that were that large or bleeding at the time of the exam. Downing testified [the victim’s] injuries were consistent with forced sexual intercourse.
Harkins was charged with third-degree sexual abuse, in violation of Iowa Code section 709.4 (2005). At the trial Harkins testified he remembered everything about the evening in question. He stated he and [the victim] had engaged in consensual sex. He stated that in the middle of having sex, he found out [the victim] had recently had sex with Derrick, and he made a derogatory comment to her. He stated [the victim] got mad and threw him out.
A jury found Harkins guilty of third-degree sexual abuse. Harkins was sentenced to a term of imprisonment not to exceed ten years.
State v. Harkins, No. 06-0660, 2007 WL 914032 (Iowa Ct.App. Mar. 28, 2007).
After the court of appeals affirmed Har-kins’s conviction, the district court imposed a special life sentence on Harkins pursuant to Iowa Code section 903B.1 (Supp.2005), in addition to the original ten-year term of imprisonment. Harkins appealed the special sentence, asserting it was unconstitutional and that his counsel was ineffective for failing to object to it. On July 22, 2009, the court of appeals rejected these arguments and again affirmed the district court. State v. Harkins, 786 N.W.2d 498, 502 (Iowa Ct.App.2009).
Having been unsuccessful on his direct appeals, Harkins filed an application for postconviction relief. There he alleged four different bases for ineffective assistance, including an allegation that his counsel should have advised him not to testify at trial. The application was denied by the district court, and that denial was affirmed by the court of appeals on January 22, 2010. Harkins v. State, No. 08-2048, 2010 WL 200408 (Iowa CtApp. Jan. 22, 2010).
Meanwhile, Harkins was incarcerated in the Mount Pleasant Correctional Facility. During 2007 and the first part of 2008, Harkins remained on the waiting list for the institution’s sex offender treatment program (SOTP). On or about July 2, 2008, an opening in the SOTP became available. Harkins alleges, and the State does not dispute, that before he could participate in the program, Harkins had to sign a “Treatment Contract,” in which he “agree[d] to be completely honest and assume full responsibility for [his] offenses and [his] behavior.” Harkins refused to sign the contract and to participate in the SOTP. In response, on July 9, 2008, the Iowa Department of Corrections (IDOC) suspended Harkins’s earned time pursuant to Iowa Code section 903A.2(l)(a) (2007).
Section 903A.2(l)(a) states an inmate under the control of IDOC serving a category “A” sentence1 is eligible for earned-time credit “equal to one and two-tenths *517days for each day the inmate demonstrates good conduct and satisfactorily participates in any program ... identified by the director [of the department of corrections].” In addition to this general statement, the statute also provides that “an inmate required to participate in a sex offender treatment program shall not be eligible for a reduction of sentence unless the inmate participates in and completes a sex offender treatment program established by the director.” Iowa Code § 903A.2(l)(a).
Following the suspension of his earned time, Harkins filed the application for postconviction relief at issue in this appeal. Harkins argued, essentially, that the suspension of his earned-time credits for failure to participate in the SOTP violated his Fifth Amendment privilege against self-incrimination. In particular, Harkins alleged:
I have maintained innocen[c]e since day one. I had my appeal and am now going through postconviction relief with my case. I cannot enter treatment because this would be an admission of guilt and would perjur[e] myself in changing my story. Also it would hinder any chance at a new trial if I would sign a confession.
The district court granted Harkins’s application in part and denied it in part. The district court determined that by conditioning Harkins’s earned time upon his participation in the SOTP, in which Har-kins would be required to acknowledge his criminal conduct, the State was unconstitutionally compelling Harkins to give testimony. However, the district court found the testimony would be potentially incriminating only until March 21, 2009, i.e., the last day on which the State could prosecute Harkins for perjury based upon his 2006 trial testimony. See Iowa Code § 802.3 (three-year statute of limitations). Accordingly, the district court ordered Harkins’s earned time to be reinstated from July 9, 2008 through March 21, 2009, but suspended as of March 22, 2009, until he participated in and completed the SOTP.
Both Harkins and the State filed petitions for a writ of certiorari. Harkins argued the district court should not have suspended his accrual of earned time as of March 22, 2009. The State, in turn, argued the district court should have upheld its original decision to suspend Harkins’s earned time as of July 9, 2008, the date when he refused to enter the treatment program. We granted the two petitions and consolidated the proceedings.
II. Standard of Review.
We normally review certiorari actions for correction of errors at law. Iowa R. Civ. P. 6.907; Johnson v. Iowa Dist. Ct., 756 N.W.2d 845, 847 (Iowa 2008). However, we have recognized a general exception to this standard of review when a certiorari action is brought alleging a violation of a constitutional right. State v. Cullison, 227 N.W.2d 121, 126 (Iowa 1975). In these circumstances, we make an independent evaluation of the totality of the circumstances under which the challenged ruling on the constitutional right was made. Id. That is, when a constitutional issue is presented, the evidence relevant to that issue is reviewed de novo. Lewis v. Iowa Dist. Ct., 555 N.W.2d 216, 218 (Iowa 1996).
III. Discussion and Analysis.
A. General Framework of Fifth Amendment Analysis. The Fifth Amendment, whose text we have quoted above, applies to the State of Iowa through the Due Process Clause of the Fourteenth Amendment to the United States Constitu*518tion.2 State v. Walls, 761 N.W.2d 688, 685 (Iowa 2009) (citing Malloy v. Hogan, 378 U.S. 1, 6, 84 S.Ct. 1489, 1492, 12 L.Ed.2d 653, 658 (1964)). The Fifth Amendment’s guarantees extend to Harkins despite his conviction and imprisonment. Minnesota v. Murphy, 465 U.S. 420, 426, 104 S.Ct. 1136, 1141, 79 L.Ed.2d 409, 418 (1984).
In order for a party to show a violation of the privilege against self-incrimination, that party must show that he or she is being compelled to give testimony that presents an impermissible risk of incriminating him or her. See Hiibel v. Sixth Judicial Dist., 542 U.S. 177, 189, 124 S.Ct. 2451, 2460, 159 L.Ed.2d 292, 305 (2004) (“To qualify for the Fifth Amendment privilege, a communication must be testimonial, incriminating, and compelled.”).
As a general rule, compulsion is present when the state threatens to inflict “potent sanctions” unless the constitutional privilege is waived or threatens to impose “substantial penalties” because a person elects to exercise that privilege. Lefkowitz v. Cunningham, 431 U.S. 801, 805, 97 S.Ct. 2132, 2135-36, 53 L.Ed.2d 1, 7 (1977).
Thus, in a series of decisions, the U.S. Supreme Court has held that states may not penalize an individual by taking away his or her government employment, professional license, or certain other rights and privileges in direct response to the individual’s assertion of Fifth Amendment rights. See id. at 807, 97 S.Ct. at 2136, 53 L.Ed.2d at 8 (loss of the right to participate in political associations and hold public office); Lefkowitz v. Turley, 414 U.S. 70, 82, 94 S.Ct. 316, 324-25, 38 L.Ed.2d 274, 284 (1973) (ineligibility to receive government contracts); Uniformed Sanitation Men Ass’n, Inc. v. Comm’r of Sanitation, 392 U.S. 280, 284, 88 S.Ct. 1917, 1920, 20 L.Ed.2d 1089, 1092 (1968) (loss of employment); Spevack v. Klein, 385 U.S. 511, 516, 87 S.Ct. 625, 628, 17 L.Ed.2d 574, 578 (1967) (revocation of a professional license). In each instance, the government’s threatened penalty jeopardized the individual’s current livelihood or professional status, and the penalty was specifi*519cally tied to the exercise of Fifth Amendment rights.
This case is somewhat different. Har-kins is not a free man, but is presently serving a ten-year term of imprisonment. The question concerns his eligibility for earned-time credits that might reduce that sentence. Also, the suspension of credits is not a direct result of Harkins’s invocation of his privilege against self-incrimination, but rather his refusal to participate in a SOTP where the SOTP requires assumption of responsibility. No one disputes that the SOTP was established for bona fide rehabilitative purposes, or that requiring the offender to acknowledge responsibility for his offense serves one of those purposes. Another U.S. Supreme Court decision provides guidance here.
B. McKune v. Lile. In McKune v. Lile, 536 U.S. 24, 122 S.Ct. 2017, 153 L.Ed.2d 47 (2002), the U.S. Supreme Court addressed Fifth Amendment rights in the context of a prison rehabilitation program for convicted sex offenders. In that case, the Court found the Kansas Department of Corrections (KDOC) did not violate the constitutional rights of Lile, a convicted sex offender, when it threatened to curtail Life’s prison privileges unless he participated in rehabilitative treatment that required him to disclose his past sex offenses. The privileges at stake included visitation rights, earnings, work opportunities, ability to send money to family, canteen expenditures, and access to a personal television. McKune, 536 U.S. at 30-31, 122 S.Ct. at 2023, 153 L.Ed.2d at 55 (plurality opinion). In addition, because Life refused to undergo the treatment, he was going to be transferred to a maximum-security unit where his movement would be more limited, he would have four as opposed to two cellmates, and he would be in a potentially more dangerous environment. Id. The Court held that depriving Lite of these various privileges because of his refusal to participate in the treatment would not violate Lite’s Fifth Amendment right against self-incrimination. Id. at 47-48, 122 S.Ct. at 2032, 153 L.Ed.2d at 66; id. at 54, 122 S.Ct. at 2035, 153 L.Ed.2d at 70 (O’Connor, J., concurring). The Court also recognized the possibility that Kansas could grant use immunity for statements made in the course of treatment as a way of avoiding potential Fifth Amendment problems, but found this was not constitutionally required. Id. at 34-35, 122 S.Ct. at 2025, 153 L.Ed.2d at 57-58 (plurality opinion).
McKune did not produce a majority opinion. Justice Kennedy wrote for four of the justices in the majority, Justice Stevens spoke for four dissenting justices, and Justice O’Connor, writing separately from the other eight justices, concurred in the judgment upholding the actions of the KDOC.
Justice Kennedy’s plurality opinion initially noted the benefits of sex offender treatment. There is a high rate of recidivism among untreated sex offenders and a broad range of agreement among therapists and correctional officers that clinical rehabilitation programs “can enable sex offenders to manage their impulses and in this way reduce recidivism.” Id. at 32-33, 122 S.Ct. at 2024, 153 L.Ed.2d at 56-57. He further pointed out:
An important component of those rehabilitation programs requires participants to confront their past and accept responsibility for their misconduct.... Research indicates that offenders who deny all allegations of sexual abuse are three times more likely to fail in treatment than those who admit even partial complicity.
Id. at 33, 122 S.Ct. at 2024, 153 L.Ed.2d at 57 (citations omitted). Thus, Justice Kennedy described the offender’s “acceptance *520of responsibility for past offenses” as “[t]he critical first step.” Id. at 33, 122 S.Ct. at 2025,153 L.Ed.2d at 57.
Justice Kennedy also observed that, while the Fifth Amendment applies to everyone, “the fact of a valid conviction and the ensuing restrictions on liberty are essential to the Fifth Amendment analysis.” Id. at 36,122 S.Ct. at 2026, 153 L.Ed.2d at 59. He added, “[R]ehabilitation is a legitimate penological interest that must be weighed against the exercise of an inmate’s liberty.” Id.
After setting out these basic parameters, Justice Kennedy concluded that the Kansas program, as administered by Kansas prison officials, did not amount to “unconstitutional compulsion.” As he explained:
A prison clinical rehabilitation program, which is acknowledged to bear a rational relation to a legitimate penological objective, does not violate the privilege against self-incrimination if the adverse consequences an inmate faces for not participating are related to the program objectives and do not constitute atypical and significant hardships in relation to the ordinary incidents of prison life.
Id. at 37-38, 122 S.Ct. at 2027, 153 L.Ed.2d at 60. Justice Kennedy also noted that Lile’s decision not to participate did not “affect his eligibility for good-time credits or parole.” Id. at 38, 122 S.Ct. at 2027, 153 L.Ed.2d at 60. In this part of his opinion, Justice Kennedy borrowed from earlier language in Sandin v. Conner, 515 U.S. 472, 484, 115 S.Ct. 2293, 2300, 132 L.Ed.2d 418, 430 (1995), which held that challenged prison conditions cannot give rise to a due process violation unless they impose “atypical and significant hardship on the inmate in relation to the ordinary incidents of prison life.”
Yet Justice Kennedy also declined to treat the compulsion inquiry as simply a comparison between the individual’s conditions after he or she invoked Fifth Amendment rights and a preexisting “baseline.” McKune, 536 U.S. at 45-47, 122 S.Ct. at 2031-32, 153 L.Ed.2d at 65. Such an approach was unsatisfactory, because compulsion involved “a question of judgment.” Id. at 41, 122 S.Ct. at 2028, 153 L.Ed.2d at 62. Often, the criminal process presents defendants with “choices” that do not give rise to a Fifth Amendment claim. Id. at 41, 122 S.Ct. at 2029, 153 L.Ed.2d at 62.
Justice Kennedy pointed to several instances within the criminal justice system where the government has been allowed to impose quite serious consequences on defendants who stand on their Fifth Amendment rights. Id. at 42-43, 122 S.Ct. at 2029-30, 153 L.Ed.2d at 63 (citing Ohio Adult Parole Auth. v. Woodard, 523 U.S. 272, 118 S.Ct. 1244, 140 L.Ed.2d 387 (1998) (allowing death row inmate’s silence at a clemency hearing to be used against him); Minnesota v. Murphy, 465 U.S. 420, 104 S.Ct. 1136, 79 L.Ed.2d 409 (1984) (no constitutional violation in requiring defendant to be truthful with the probation officer in all matters as a condition of probation); Baxter v. Palmigiano, 425 U.S. 308, 96 S.Ct. 1551, 47 L.Ed.2d 810 (1976) (permitting punitive segregation and downgrade of prison classification status based on silence at a prison disciplinary hearing)). As Justice Kennedy put it, “The parties in Woodard, Murphy, and Baxter all were faced with ramifications far worse than respondent faces here, and in each of those cases the Court determined that their hard choice between silence and the consequences was not compelled.” Id. at 44-45, 122 S.Ct. at 2030, 153 L.Ed.2d at 64. Also, in the federal criminal system, defendants typically receive a downward adjustment in their sentence for pleading guilty, and conversely suffer a longer sentence if they do not plead guilty, but this feature is *521“accepted” and not regarded as a violation of the defendant’s Fifth Amendment rights. Id. at 47, 122 S.Ct. at 2032, 153 L.Ed.2d at 65-66.
In the concluding paragraphs of his opinion, Justice Kennedy returned to his initial themes and summarized as follows:
Acceptance of responsibility is the beginning of rehabilitation. And a recognition that there are rewards for those who attempt to reform is a vital and necessary step toward completion. The Court of Appeals’ ruling would defeat these objectives....
The Kansas SATP [Sexual Abuse Treatment Program] represents a sensible approach to reducing the serious danger that repeat sex offenders pose to many innocent persons, most often children. The State’s interest in rehabilitation is undeniable. There is, furthermore, no indication that the SATP is merely an elaborate ruse to skirt the protections of the privilege against compelled self-incrimination. Rather, the program allows prison administrators to provide to those who need treatment the incentive to seek it.
Id. at 47-48, 122 S.Ct. at 2032, 153 L.Ed.2d at 66.
In short, for the plurality represented by Justice Kennedy’s opinion, the loss of various prison privileges clearly did not amount to compulsion because such deprivations were not “atypical and significant hardships in relation to the ordinary incidents of prison life.” Id. at 38, 122 S.Ct. at 2027, 153 L.Ed.2d at 60. But the plurality also indicated that degree of hardship was not the ultimate question, and they did not define the outer limits of what prison officials could do to encourage participation in a sex offender treatment program. Taken as a whole, the plurality opinion approves the state’s use of incentives — even “hard ehoice[s],” id. at 45, 122 S.Ct. at 2030, 153 L.Ed.2d at 64 — to obtain participation in sex offender treatment programs requiring acceptance of responsibility.
Justice Stevens, writing for four dissenting justices, strenuously disagreed with the plurality’s view that Lile’s threatened loss of privileges did not amount to unconstitutional compulsion. He acknowledged that the SATP “clearly serves legitimate therapeutic purposes.” Id. at 68, 122 S.Ct. at 2043, 153 L.Ed.2d at 79 (Stevens, J., dissenting). As he put it, “Mental health professionals seem to agree that accepting responsibility for past sexual misconduct is often essential to successful treatment, and that treatment programs can reduce the risk of recidivism by sex offenders.” Id. Yet he concluded that Kansas could not “punish an inmate’s assertion of his Fifth Amendment privilege with the same mandatory sanction that follows a disciplinary conviction for an offense such as theft, sodomy, riot, arson, or assault.” Id. at 54, 122 S.Ct. at 2035-36, 153 L.Ed.2d at 70.
Justice Stevens pointed out that Lile’s shift to a maximum-security unit and his loss of visitation and the ability to earn up to minimum wage in the present case amounted to “a serious loss of tangible privileges.” Id. at 63-64, 122 S.Ct. at 2040-41, 153 L.Ed.2d at 76. He added, “[T]he sanctions are in fact severe, but even if that were not so, the plurality’s policy judgment does not justify the evisceration of a constitutional right.” Id. at 54, 122 S.Ct. at 2036, 153 L.Ed.2d at 70-71. Justice Stevens also disagreed with the proposition that the prior criminal justice cases like Woodard and Baxter were relevant because they had upheld the imposition of sanctions on prisoners who asserted Fifth Amendment rights. In his view, there was an important distinction between the mandatory, official sanction present in Lile’s case and “a mere risk of *522adverse consequences stemming from a voluntary choice” in cases like Woodard, Murphy, and Baxter. Id. at 59-62, 122 S.Ct. at 2038-40,153 L.Ed.2d at 73-75. In Woodard, for example, the inmate’s invocation of Fifth Amendment rights in the clemency proceeding could be held against him, but adverse consequences were not “automatic.” Id. at 59-60, 122 S.Ct. at 2038-39, 153 L.Ed.2d at 74. Justice Stevens also stated that Kansas could achieve its objectives without impinging on the Fifth Amendment privilege by granting-use immunity to participants. Id. at 69-70, 122 S.Ct. at 2043-44, 153 L.Ed.2d at 80.
Justice O’Connor took a third approach. In the first part of her concurrence, she expressed the view that the penalties Lile faced were not “sufficiently serious to compel his testimony.” Id. at 52, 122 S.Ct. at 2034, 153 L.Ed.2d at 69 (O’Connor, J., concurring). This was a sufficient basis for her to uphold the actions of the KDOC and concur in the result. Nonetheless, she went on to criticize the plurality for suggesting that more serious consequences such as “longer incarceration and execution” could not constitute unconstitutional compulsion. Id.
Yet Justice O’Connor also criticized the dissent for its inability to draw a reasoned distinction between the “criminal justice” cases such as Woodard, Murphy, and Baxter — which upheld more severe sanctions than those imposed on Lile (e.g., loss of life in Woodard) — and the “penalty” eases such as Cunningham, Turley, Uniformed Sanitation Men, and Spevack. Id. at 52, 122 S.Ct. at 2035, 153 L.Ed.2d at 69. She agreed with the plurality that the inmates in Woodard, Murphy, and Baxter, as a practical matter, faced more onerous penalties; the dissenters’ attempt to distinguish those cases on the ground that the penalties there were not “automatic” did not persuade her. Id.
In Justice O’Connor’s view, the critical issue for Fifth Amendment purposes was not necessarily the actual penalty or sanction, but the context within which it was imposed. She elaborated:
I believe the proper theory [of the Fifth Amendment privilege against self-incrimination] should recognize that it is generally acceptable to impose the risk of punishment, however great, so long as the actual imposition of such punishment is accomplished through a fair criminal process.... Forcing defendants to accept such consequences seems to me very different from imposing penalties for the refusal to incriminate oneself that go beyond the criminal process and appear, starkly, as government attempts to compel testimony; in the latter context, any penalty that is capable of compelling a person to be a witness against himself is illegitimate.
Id. at 53, 122 S.Ct. at 2035, 153 L.Ed.2d at 69-70.
Under the narrowest grounds doctrine, the holding of a fragmented Supreme Court decision with no majority opinion “ ‘may be viewed as that position taken by those Members who concurred in the judgments on the narrowest grounds.’ ” Marks v. United States, 430 U.S. 188, 193, 97 S.Ct. 990, 993, 51 L.Ed.2d 260, 266 (1977) (quoting Gregg v. Georgia, 428 U.S. 153, 169 n. 15, 96 S.Ct. 2909, 2923, n. 15, 49 L.Ed.2d 859, 872 n. 15 (1976) (opinion of Stewart, Powell, and Stevens, JJ.)). Justice O’Connor’s concurrence therefore controls here.
As we read Justice O’Connor’s concurrence, “compulsion” is not a simple, straightforward continuum based on the severity of the sanction. Rather, under a “proper theory,” the critical questions are *523whether the sanction was “accomplished through a fair criminal process” and whether the state was engaged in a “stark[]” attempt to compel testimony. McKune, 536 U.S. at 53, 122 S.Ct. at 2035, 153 L.Ed.2d at 69 (O’Connor, J., concurring). Justice O’Connor thus appears to allow for the possibility that individuals who have been convicted through a “fair criminal process” can suffer significant adverse consequences, including a potentially longer period of incarceration, for choosing not to acknowledge their offense, provided the state was not engaged in a direct effort to compel testimony. See also id. at 53, 122 S.Ct. at 2035, 153 L.Ed.2d at 70 (Justice O’Connor noting that the federal sentencing guidelines offer the potential benefit of a lower sentence in exchange for the defendant’s acceptance of responsibility).
In this regard, Justice O’Connor’s concurrence shares considerable ground with Justice Kennedy’s plurality opinion. Both opinions, in the end, do not regard compulsion as a simple “How serious is the consequence?” inquiry. Rather, both of them recognize that a fair criminal process may impose difficult choices on defendants to serve a valid penological goal, without crossing the line into unconstitutional compulsion.
C. Post -McKune Decisions of Federal Appellate Courts. In the wake of McKune, a number of federal appellate courts have had to decide whether it violates the Fifth Amendment when a sex offender receives more prison time, rather than just stricter prison conditions, because he or she refused to participate in a treatment program that required him or her to admit past sex crimes. For the most part, based on their understanding of the scope of McKune, they have rejected these Fifth Amendment claims.
In Searcy v. Simmons, 299 F.3d 1220 (10th Cir.2002), a case that had been held by the appellate court pending McKune, the Tenth Circuit concluded a Kansas sex offender’s loss of the ability to earn good-time credits because he refused to accept responsibility for his crime and disclose other possible sex crimes did not violate the Fifth Amendment. The court acknowledged that this specific situation was not expressly covered by McKune. Searcy, 299 F.3d at 1225. Nonetheless, applying Justice O’Connor’s concurrence as the dispositive opinion, the court found that Searcy had been convicted in a “fair criminal process,” and “[wjhile the potential for incrimination is not disputed, there is no assertion that the KDOC is using the SATP as a surreptitious means to obtain evidence for criminal prosecutions.” Id. at 1226-27. As the court explained:
Mr. Searcy’s lost privileges and lost opportunity to earn future good time credits are quite simply not the result of his refusal to incriminate himself, but are a consequence of his inability to complete rehabilitation the KDOC has determined — in light of the serious offense for which Mr. Searcy was convicted — is in the best interest for Mr. Searcy and society.
Id. at 1227.
Ainsworth v. Stanley, 317 F.3d 1 (1st Cir.2002), decided on remand after McKune, reached a similar outcome. There the First Circuit held New Hampshire could constitutionally deny parole in most instances to sex offenders who refused to accept responsibility for their crimes. That court commented that “Justice O’Connor does not purport to lay out any abstract analysis or unifying theory that would prefigure her views regarding the constitutionality of New Hampshire’s program,” and therefore “we have no clear guideposts.” Ainsworth, 317 F.3d at 4. Hence, the First Circuit deferred to its previously expressed view that under recent decisions of the U.S. Supreme Court, *524the compulsion analysis “is more circumscribed in the prison context” and only “unreasonable” burdens are proscribed. Id. at 5. Reiterating its pre-McKune approach, the First Circuit concluded that New Hampshire could subject sex offenders who refused to participate in treatment that required acceptance of responsibility to the likelihood of a longer period of incarceration, because the overall burden was not unreasonable in light of the relevant circumstances, including “the voluntary nature of the program” (i.e., participation is a choice) and the state’s “valid” interest in effective rehabilitation. Id. at 5-6.
Although the First Circuit purported to be following its own earlier precedents rather than Justice O’Connor’s concurrence, one can argue that its analytical approach is not that different from hers. The “factors” mentioned in its opinion, i.e., that the defendant was presented with a choice within a fair criminal process and that the state’s purpose was not testimonial, surface also in Justice O’Connor’s discussion of “proper theory” of the Fifth Amendment. McKune, 536 U.S. at 53, 122 S.Ct. at 2035,153 L.Ed.2d at 69 (O’Connor, J., concurring).
A few years later, in Entzi v. Redmann, 485 F.3d 998 (8th Cir.2007), the Eighth Circuit denied a sex offender’s claim that North Dakota violated his Fifth Amendment rights by withholding sentence-reduction credits when he refused to report to a sex offender education class where he would have had to admit his offense. Relying expressly on Searcy and Justice O’Connor’s concurrence in McKune, the court found that the loss of an opportunity for a discretionary sentence-reduction credit “is not among the consequences for noncompliance that go ‘beyond the criminal process and appear, starkly, as government attempts to compel testimony.’ ” Entzi, 485 F.3d at 1004 (quoting McKune, 536 U.S. at 53, 122 S.Ct. at 2035, 153 L.Ed.2d at 69 (O’Connor, J., concurring)). This court found, therefore, no unconstitutional compulsion. Id.
Likewise, in DeFoy v. McCullough, 301 Fed.Appx. 177 (3rd Cir.2008), the Third Circuit upheld Pennsylvania’s denial of re-paróle to a sex offender based in part on the offender’s refusal to participate in a treatment program. The treatment program would have required the inmate to admit his guilt even though he had obtained a new trial on the underlying charges. DeFoy, 301 Fed.Appx. at 178. Applying Justice O’Connor’s concurrence, the court reasoned that no unconstitutional compulsion had occurred. DeFoy’s sentence was not extended; he “merely had to serve the rest of his sentence, imposed through a fair criminal process.” Id. Furthermore, “DeFoy was not denied reparole because he invoked the Fifth Amendment, but rather, primarily because he chose not to participate in treatment.” Id. at 182. Thus, the considerations noted by Justice O’Connor in her concurrence — i.e., the sanction merely forced the prisoner to serve out a sentence imposed in a fair criminal process, the prisoner was given a choice, and the purpose of the program was truly rehabilitative rather than to obtain testimony, see McKune, 536 U.S. at 53, 122 S.Ct. at 2035, 153 L.Ed.2d at 69 (O’Connor, J., concurring) — were disposi-tive in overruling the Fifth Amendment claim.3 DeFoy, 301 Fed.Appx. at 182.
*525The Ninth Circuit reached a different result in United States v. Antelope, 395 F.3d 1128 (9th Cir.2005), but the facts there were somewhat different. The defendant had pled guilty to possession of child pornography and was required to participate in a treatment program as a condition of obtaining supervised release. Antelope, 395 F.3d at 1131. The defendant had no Fifth Amendment objection to admitting the crime of which he had been convicted, but objected to having to disclose other potential criminal conduct in the course of the program. Id. Although the court found a violation of the defendant’s right against self-incrimination, its overall interpretation of O’Connor’s concurrence does not appear to vary from that of the other circuits. To the contrary, the Ninth Circuit found that under her concurrence,
the compulsion inquiry does not disposi-tively turn on the status of the person claiming the Fifth Amendment privilege or on the severity of the penalty imposed, although these factors may bear on the analysis. Instead, the controlling issue is the state’s purpose in imposing the penalty: Although it may be acceptable for the state to impose harsh penalties on defendants when it has legitimate reasons for doing so consistent with their conviction for their crimes of incarceration, it is a different thing to impose “penalties for the refusal to incriminate oneself that go beyond the criminal process and appear, starkly, as government attempts to compel testimony.”
id at 1137 (quoting McKune, 536 U.S. at 53, 122 S.Ct. at 2035, 153 L.Ed.2d at 69 (O’Connor, J., concurring)). A crucial point for the Ninth Circuit was that the federal government was sanctioning “Antelope for his self-protective silence about conduct that might constitute other crimes.” Id. These kinds of disclosures, the Ninth Circuit felt, were “starkly incriminating” regardless of their potential rehabilitative purpose. Id. at 1138.
D. Post -McKune Decisions of State Appellate Courts. In addition to these five federal appellate courts, several state appellate courts have addressed whether a Fifth Amendment violation occurs when a convicted sex offender’s release date is adversely affected because the offender refused to participate in a treatment program that required admission of responsibility. The results have been more divided. Some courts have found no Fifth Amendment violation. See, e.g., People v. Lehmkuhl, 117 P.3d 98, 108 (Colo.Ct.App. 2004); Spencer v. State, 334 S.W.3d 559, 568 (Mo.Ct.App.2010); Dzul v. State, 118 Nev. 681, 56 P.3d 875, 884-85 (2002); Wilson v. Pa. Bd. of Prob. & Parole, 942 A.2d 270, 273 (Pa.Commw.Ct.2008); State v. Pritchett, 69 P.3d 1278, 1286-87 (Utah 2003). Others have. See, e.g., James v. State, 75 P.3d 1065, 1068 (Alaska Ct.App. 2003) (state conceded compulsion); Bender v. N.J. Dep’t of Corr., 356 N.J.Super. 432, 812 A.2d 1154, 1160-61 (App.Div.2003); State ex rel. Tate v. Schwarz, 257 Wis.2d 40, 654 N.W.2d 438, 442-45 (2002).
*526In Johnson v. Fabian, 735 N.W.2d 295 (Minn.2007), cited by the district court below, the Minnesota Supreme Court held that convicted sex offenders could not have their sentences extended beyond their presumptive terms based on their refusal to participate in sex offender treatment programs that would have required them to admit their crimes.
Johnson involved two consolidated appeals of defendants who had been convicted of criminal sexual conduct. Each received an “executed sentence,” which under Minnesota’s sentencing scheme typically equated to a term of actual imprisonment of two-thirds that amount. 735 N.W.2d at 299. The term of actual imprisonment was subject to extension if the defendant committed a disciplinary offense while incarcerated. Id. When the defendants refused to participate in Minnesota’s sex offender treatment program, those refusals were considered disciplinary violations, and their terms of actual imprisonment were extended by forty-five days. Id. at 298. The defendants challenged these extensions as violating their Fifth Amendment rights.
In assessing the defendants’ Fifth Amendment claims, the Johnson court agreed that McKune was the relevant precedent. But it declined to follow the “comments about sanctions that extend the term of incarceration” in both the plurality opinion and Justice O’Connor’s opinion on the grounds they were dicta. Id. at 304. Instead, the Johnson court ultimately concluded that under both opinions, “atypical and significant hardship” was the relevant benchmark. Id. at 304-05. That is, if the sanction amounted to such a hardship, it was “compulsion”; if not, it was not. Id. As the Minnesota court put it:
[I]t is clear to us that a majority composed of the plurality and Justice O’Con-nor (and likely the dissenting Justices as well) agreed in McKune that consequences that impose atypical and significant hardship in prison constitute compulsion for purposes of the Fifth Amendment.
Id. at 306. The court then went on to hold that forty-five days of additional incarceration met the “atypical and significant hardship” test and therefore constituted unconstitutional compulsion. Id. at 306-09.
Two dissenting justices in Johnson disagreed with their colleagues’ reading of McKune. They maintained that neither the plurality nor Justice O’Connor had endorsed “atypical and significant hardship” as the standard for whether compulsion was present. Id. at 313. At most, the presence of such a hardship was a necessary but not sufficient condition for finding compulsion. Id. Discerning “no clear guideposts” in McKune, the dissenters argued that Minnesota should continue to follow its pre-McKune precedent that extending an inmate’s supervised release date due to his failure to participate in a sex offender program was not “compulsion” in violation of the Fifth Amendment. Id. at 312-14 (citing State ex rel. Morrow v. LaFleur, 590 N.W.2d 787, 789 (Minn. 1999)). The dissent elaborated:
Numerous federal circuit courts have considered this issue and held that extension of a supervised release date for failure to participate in treatment is not compulsion. While the majority cites cases that have held differently, I find that the Supreme Court has not spoken clearly on this issue, nor is there a national consensus that would compel us to overturn Morrow. I would hold that extending an inmate’s supervised release date because of his failure to participate in a sex offender treatment program does not rise to the level of compulsion necessary to violate the inmate’s Fifth *527Amendment privilege against self-incrimination.
Id. at 815 (citations omitted).
We have some difficulty squaring the Johnson majority’s interpretation of McKune with our own. While neither Justice Kennedy nor Justice O’Connor in McKune precisely delineated the permissible outer limits of “compulsion” in the prison context, neither indicated that imposing an “atypical and significant hardship” would automatically cross those limits. To the contrary, both opinions noted that in prior cases, like Woodard, states had been allowed to impose far more serious consequences, such as a potential loss of clemency, on inmates who chose to exercise their Fifth Amendment rights. Thus, both opinions found that the question of compulsion had to be analyzed in context, with particular emphasis (according to Justice O’Connor) on whether the consequence arose as a choice afforded by a fair criminal process and whether the underlying purpose was rehabilitative rather than the compulsion of testimony. In our view, the respective decisions of the Tenth, Eighth, and Third Circuits in Searcy, Ent-zi, and DeFoy more accurately reflect this approach.
E. Applying McKune to This Case. Based on our reading of McKune, we find no Fifth Amendment violation here. The requirement that Harkins participate in the SOTP to be eligible for earned-time credits was part of “a fair criminal process.” McKune, 536 U.S. at 53, 122 S.Ct. at 2035, 153 L.Ed.2d at 69 (O’Connor, J., concurring). Section 903A.2(l)(a), which established this requirement, was the law both when Harkins was alleged to have sexually assaulted his victim, and when he was convicted of doing so. Thus, from the moment Harkins committed his crime, it was clear that if he was convicted and chose not to participate in the prescribed treatment program, he would not be eligible for earned-time credits. That was the set of consequences for his conduct prescribed by the legislature.
Encouraging a convicted sex offender to participate in a SOTP where he has to acknowledge his crime also serves important rehabilitative goals. The State of Iowa is not “starkly ... attempting] to compel testimony.” Id. Rather, the undisputed purpose of the program is to get the offender to confront his or her past behavior so it does not reoccur. Harkins does not claim that he will be forced to disclose other, as-yet-unknown sex offenses. Cf Antelope, 395 F.3d at 1137. In fact, the only admission the State could obtain here is one it almost certainly does not need, since Harkins has been convicted and his conviction has been upheld on direct appeal.
The specifics of this case illustrate what the legislature might have had in mind when it enacted section 903A.2(l)(a). The evidence, summarized above, supports a finding that Harkins committed a rather violent sexual assault. Harkins’s original story to the police was that he had not had sexual relations with the victim. At trial, Harkins changed course and admitted having had sex with the victim, but claimed it was consensual. Now, according to a memo that is part of the record, Harkins maintains, “I am not guilty and am not going to take the program.” Under these circumstances, a rehabilitation program requiring the offender to confront his past offense might be particularly beneficial. We do not see the Fifth Amendment as a barrier to an earned-credit incentive for Harkins to participate in such a program.
Both the plurality and the special concurrence in McKune indicated that compulsion in the prison setting is not a simple question of, “How big is the stick or carrot?” Instead, Justice Kennedy and Jus*528tice O’Connor recognized that a convicted criminal defendant may be confronted with choices, such as whether to take the stand at a clemency hearing or whether to participate in sex offender treatment, which might be considered compulsion in other circumstances, but are deemed legitimate exercises of state authority here. We therefore need to ask whether the choice arose as a result of the defendant’s conviction within the criminal justice system and whether imposing the choice serves a proper goal of that system. We have and we believe the answers are clear.
Thus, while a loss of eligibility for earned-time credits clearly “implicates a liberty interest,” Reilly v. Iowa Dist. Ct, 783 N.W.2d 490, 496 (Iowa 2010), it does not equate in this case with unconstitutional compulsion. The State is not using a threatened loss of credits to try to extract testimony; instead, it is attempting to administer a bona fide rehabilitation program for sex offenders who have already been found guilty under a statutory scheme that afforded them all required due process.
We also find support for this conclusion in In re C.H., 652 N.W.2d 144 (Iowa 2002), where we addressed a father’s claim that his Fifth Amendment rights had been violated when his parental rights were terminated after he failed to complete a sex offender treatment program. We made clear that “sexual offender treatment where the offender refuses to take responsibility for the abuse may constitute ineffective therapy,” and that the State of Iowa could terminate parental rights based on a parent sex offender’s “failure to obtain treatment for his or her problems.” In re C.H., 652 N.W.2d at 150. We specifically noted that “a person’s exercise of a constitutional right may indeed have consequences” — without resulting in a Fifth Amendment violation. Id. Just as in C.H., where we held that a father who failed to complete a treatment program due to his assertion of Fifth Amendment rights could suffer loss of parental rights, so here we hold that a convicted sex offender who failed to complete a treatment program due to his assertion of Fifth Amendment rights may constitutionally have his eligibility for earned-time credits suspended. If the loss of parental rights does not amount to unconstitutional compulsion, it is difficult to see how the suspension of earned-time credits would either — so long as in both cases the State is not simply trying to obtain testimony for future use.4
IV. Conclusion.
Harkins had every right not to be a witness against himself, a right he actually chose to waive at trial by taking the stand. Now that he has been convicted as a sex offender, though, the State of Iowa may constitutionally establish an incentive for him to obtain treatment in prison by withholding earned-time credits if he declines to participate.
For the foregoing reasons, we sustain the writ requested by the State, we set aside the district court’s order to the ex*529tent it reinstated Harkins’s earned time for the period July 9, 2008, through March 21, 2009, and we remand for further proceedings consistent herewith.
STATE’S WRIT SUSTAINED; HAR-KINS’S WRIT ANNULLED; CASE REMANDED.
All justices concur except WIGGINS, HECHT, and APPEL, JJ., who dissent.. Harkins is serving a category "A" sentence because he is not subject to a mandatory minimum under Iowa Code section 902.12. See Iowa Code § 903A.2(l)(a).
. Although the Iowa Constitution does not contain an equivalent provision against self-incrimination, we have held such a right to be implicit in the "due process of law” guaranteed by Article I, section 9. State v. Height, 117 Iowa 650, 659, 91 N.W. 935, 938 (1902). In this case, though, neither Harkins, the State, nor the district court mentioned the Iowa Constitution. See State v. Griffin, 691 N.W.2d 734, 736 (Iowa 2005) (finding a state constitutional claim was not preserved when the Federal Constitution was the sole ground raised in the district court); State v. Wilkins, 687 N.W.2d 263, 265 (Iowa 2004) (same).
Harkins's original application for postcon-viction relief did not cite legal authority but simply alleged self-incrimination. An unre-porled hearing was held, at which Harkins apparently cited to Johnson v. Fabian, 735 N.W.2d 295 (Minn.2007), a decision based on the Fifth Amendment. The district court then issued a ruling that addressed only the Fifth Amendment right against self-incrimination. Neither party sought to enlarge that ruling by raising the Iowa Constitution. See Iowa R. Civ. P. 1.904(2); State v. Mitchell, 757 N.W.2d 431, 435 (Iowa 2008) (holding that when a defendant argues a constitutional violation, but the district court fails to address it, it is incumbent upon the defendant to "file a motion to enlarge the trial court's findings or in any other manner have the district court address th[e] issue”).
In its brief to us, the State maintains that "[n]o state claims have been raised, and the only issue raised is one of federal Fifth Amendment law.” Harkins has not disputed this point; to the contrary, in his pro se appellate brief he cited to the Fifth Amendment four separate times. For all these reasons, we confine our analysis to the U.S. Constitution. See State v. Palmer, 791 N.W.2d 840, 844 (Iowa 2010) (limiting a self-incrimination analysis to the Federal Constitution when no challenges under the Iowa Constitution were raised in the district court or on appeal).
. At least one of these federal appellate decisions, i.e., Searcy, involved an automatic loss of eligibility for sentence-reduction credits, similar to Iowa Code section 903A.2(l)(a). Under the program at issue in Searcy, failure to participate in the treatment program meant that the inmate forfeited eligibility for sentence-reduction credits, but (as in Iowa) participation did not guarantee a reduction in sentence. Searcy, 299 F.3d at 1223 (noting *525that an inmate who refuses to participate in a sex offender treatment program “loses the opportunity to earn any further good time credits” and "those credits ... cannot be regained”); see also Ainsworth, 317 F.3d at 3 (noting that "nonparticipation in the [sex offenders program] almost always results in an inmate being denied parole”); DeFoy, 301 Fed.Appx. at 179 (noting that "it was the rare case that parole was granted without treatment”). As we point out above, Justice O’Connor's concurrence rejects the notion urged by Justice Stevens in dissent that it makes a constitutional difference whether “the negative outcome” follows directly from “the decision to remain silent,” McKune, 536 U.S. at 52, 122 S.Ct. at 2035, 153 L.Ed.2d at 69 (O’Connor, J., concurring), or whether the decision simply makes that outcome more likely.
. It is true we said in C.H., "The State may require parents to otherwise undergo treatment, but it may not specifically require an admission of guilt as part of the treatment.” 652 N.W.2d at 150. Thus, a distinction exists between the present case, where the SOTP expressly requires acceptance of responsibility, and C.H., where the State simply required treatment and admission of responsibility was part of the treatment. Yet the more significant distinction cuts the other way. In this case, Harkins has already been convicted of a sex offense in a criminal proceeding; in C.H., the father had not been. Hence, there were more grounds for concern in C.H. about "stark[] government attempts to compel testimony.” McKune, 536 U.S. at 53, 122 S.Ct. at 2035, 153 L.Ed.2d at 69 (O'Connor, J., concurring).