Troy Dace is serving two concurrent ten year sentences in the South Dakota State Penitentiary for aggravated assault and attempted rape. On January 27, 1984, Dace became eligible for parole and he appeared before the South Dakota Board of Pardons and Parole (the Board). The Board denied Dace’s request for parole giving no reason for the denial.
Dace then brought this 42 U.S.C. § 1983 action in federal district court contending that the Board deprived him of a liberty interest without due process of law in violation of the fourteenth amendment. The district court1 dismissed his claim on the ground that the South Dakota statute, S.D. Codified Laws Ann. § 24-15-8 (1979), and regulations, S.D.Admin.R. 17:60:02:01-:09 (1979), governing parole did not provide any liberty interest and that therefore Dace was not entitled to assert a lack of due process. A panel of this court reversed the district court’s dismissal, Dace v. Mickelson, 797 F.2d 574 (8th Cir.1986), and this court en banc granted a rehearing. We now vacate the panel’s decision and affirm the district court.
In Greenholtz v. Inmates of Nebraska Penal & Correctional Complex, 442 U.S. *12791, 99 S.Ct. 2100, 60 L.Ed.2d 668 (1979), the Supreme Court held:
There is no constitutional or inherent right of a convicted person to be conditionally released before the expiration of a valid sentence. The natural desire of an individual to be released is indistinguishable from the initial resistance to being confined. But the conviction, with all its procedural safeguards, has extinguished that liberty right: “[G]iven a valid conviction, the criminal defendant has been constitutionally deprived of his liberty.” Meachum v. Fano, 427 U.S. 215, 224, 96 S.Ct. 2532, 2538, 49 L.Ed.2d 451 (1976).
442 U.S. at 7, 99 S.Ct. at 2104.
Greenholtz, however, established that a state may create a liberty interest in parole by enacting a statute which instills in an inmate an “expectancy of release.” Id. at 12, 99 S.Ct. at 2106; see also Parker v. Corrothers, 750 F.2d 653, 655 (8th Cir.1984); Evans v. Dillahunty, 662 F.2d 522, 524 (8th Cir.1981). The court further held that when a liberty interest in parole is created by the state, minimal due process considerations require that when parole is denied the board must inform the inmate of the reasons he falls short of qualifying for parole. Greenholtz, at 16, 99 S.Ct. at 2108.2
In Parker v. Corrothers, this court reviewed leading Supreme Court and Eighth Circuit cases3 and concluded:
These cases indicate that there are two standards which determine whether a statute creates a protected liberty interest in parole: (1) does the statute contain particularized substantive standards or criteria which significantly guide parole decisions; and (2) does the statute use mandatory language similar in substance or form to the Nebraska statute’s language at issue in Greenholtz ?
750 F.2d at 656; see also Nash v. Black, 781 F.2d 665, 668 (8th Cir.1986) (Parker test adopted in analyzing Missouri Department of Corrections’ refusal to transfer prisoner or to consider him for furlough). The same standards apply to a review of a state rule, regulation, or practice to find an expectancy of release. In determining whether a statute or regulation provides a liberty interest, the court must decide whether that state has placed “substantive limitations on official discretion.” Olim v. Wakinekona, 461 U.S. 238, 249, 103 S.Ct. 1741, 1747 75 L.Ed.2d 813 (1983). “An inmate must show ‘that particularized standards or criteria guide the State’s decision-makers.’ ” Id. (quoting Connecticut Board of Pardons v. Dumschat, 452 U.S. 458, 467, 101 S.Ct. 2460, 2465, 69 L.Ed.2d 158 (1981) (Brennan, J., concurring)). As the Olim court stated: “If the decision-maker is not ‘required to base its decisions on objective and defined criteria,’ but instead ‘can deny the requested relief for any constitutionally permissible reason or for no reason at all’ the State has not created a constitutionally protected liberty interest.” Olim, 461 U.S. at 249, 103 S.Ct. at 1747 (quoting Justice Brennan’s concurring opin*1280ion in Dumschat, 452 U.S. at 466-67, 101 S.Ct. at 2465).
To satisfy the first prong of the Parker test, the parole statute must contain “particularized substantive standards or criteria which significantly guide parole decisions.” Parker, 750 F.2d at 656. Substantive standards are specific, objective, measurable criteria such as length of time served, prior criminal history, seriousness of the offense, any disciplinary reports, and existence of any detainers filed against the inmate. See, e.g., id., at 658. On the other hand, general factors to be taken into consideration by a parole board which do not rise to the level of substantive guidelines include general sociological and background information such as family history, education, progress in rehabilitation programs, and ability to adjust to life outside prison. Although these are important considerations, they are subjective in nature and do not place substantive limitations on prison officials’ discretion in any measurable way.
Even if substantive guidelines are to be considered, however, unless these guidelines limit the parole board’s discretion to release the prisoner, no liberty interest in parole is established. See id., at 656. In other words, for a state to create a protectible liberty interest the statute or regulation must require release upon satisfaction of the substantive criteria listed. Such a directive may be found where the state uses language of a mandatory character, such as “shall,” “will,” or “must.” Hewitt v. Helms, 459 U.S. 460, 471, 103 S.Ct. 864, 871, 74 L.Ed.2d 675 (1983); see, e.g., Greenholtz, 442 U.S. at 11, 99 S.Ct. at 2106 (parole board “shall” release inmate “unless” one of four criteria is met and board believes that release should be deferred); Parker, 750 F.2d at 657 (“while the presence or absence of mandatory language is not necessarily talismanic, it is an important factor in determining whether a parole statute creates a liberty interest”); Evans, 662 F.2d at 525 (“important factor has been the presence or absence of mandatory language”); see also, e.g., Boothe v. Hammock, 605 F.2d 661, 663-64 (2d Cir.1979). While this mandatory language is usually found in a “shall * * * unless” or similar format,4 several other forms have been found sufficient to satisfy the mandatory language requirement. See Parker, 750 F.2d at 658 (“it is the policy” of the board to release inmates “unless” the board believes release should be deferred for any of several reasons); see also Mayes v. Trammel, 751 F.2d 175, 178 (6th Cir.1984) (board “operates under the presumption” that each prisoner is a worthy candidate for parole and “presumes he will be released” when first eligible, but parole “may” be denied “if” certain factors are met); but see Wright v. Trammell, 810 F.2d 589 (6th Cir.1987) (per curiam) (new rule makes parole release purely discretionary).
The mere use of discretionary language, however, is insufficient to establish a liberty interest. To create a liberty interest in the context of a parole release statute, regulation, or rule, it is essential that the prisoner’s release be mandated in order to fulfill the requirements of our Parker test. See, e.g., Greenholtz, 442 U.S. at 11, 99 S.Ct. at 2106 (board “shall order [prisoner’s] release’’)] Parker, 750 F.2d at 658 (“it [is] the policy of the Board to order [prisoner’s] release ”); Evans, 662 F.2d at 526 (“such prisoner shall be released”)] Williams, 661 F.2d at 698 (“the board shall release” prisoner) (emphasis added). If the statute, rule, or regulation only mandates that the state officials follow certain procedures or take into account certain factors, but specifically provides that the prisoner’s release is nevertheless discretionary with the board, as evidenced by the use of discretionary language, then no protected liberty interest has been created. See, e.g., Gale v. Moore, 763 F.2d 341, 343 (8th Cir.1985) (amended Missouri parole statute requiring consideration of certain substantive criteria but which also provides *1281that the parole board “may in its discretion release a prisoner” does not create a liberty interest); Parker, 750 F.2d at 656-57 (Arkansas statute requiring consideration of certain criteria but which provides that the parole board “may release” prisoner creates no liberty interest). We now turn to the relevant statute and regulations.
S.D. Codified Laws Ann. § 24-15-8
On January 27, 1984, the date Dace became eligible for parole, the relevant parole statute provided:
When an inmate becomes eligible for parole, he shall be called before the board of pardons and paroles to personally present his application for parole. The board may issue an order to the warden of the penitentiary that the inmate shall be paroled if it is satisfied that:
(1) The inmate has been confined in the penitentiary for a sufficient length of time to accomplish his rehabilitation;
(2) The inmate will be paroled under the supervision and restrictions provided by law for parolees, without danger to society; and
(3) The inmate has secured suitable employment or beneficial occupation of his time likely to continue until the end of the period of his parole in some suitable place within or without the state where he will be free from criminal influences. The board shall fix the time of parole for an inmate.
S.D. Codified Laws Ann. § 24-15-8 (1979).5 (Emphasis added). It should be clear that the statute does not create a protected liberty interest in parole. By establishing that the board “may” issue an order to the warden that the inmate is to be paroled, the statute makes the release of the inmate purely discretionary.6 Thus, the statute fails to meet the essential mandatory language element of Greenholtz and Parker.
S.D.Admin.R. 17:60:02:01-:09
Dace urges that since Rule 17:60:02:01 provides that the Board, in determining whether to grant parole release, “shall” consider and review (1) the inmate’s presentation of his or her needs, desires, problems, an evaluation of present progress and plans for the future, (2) all available history of the inmate, and (3) treatment alternatives or other plans for the inmate, it therefore limits the Board’s exercise of discretion to grant parole. Dace likewise relies on the listed factors that the Board may consider under Rule 17:60:02:07.7
*1282A review of these regulations, however, reveals that as with the parole statute, nowhere is a prisoner’s release mandated upon the satisfaction of specific substantive criteria. Dace contends that mandatory language similar to that found in Greenholtz is not necessary to the establishment of a protected liberty interest. We think this argument is clearly refuted by Greenholtz. In that case, the Court noted that an inmate’s request for parole “shall” be granted under the Nebraska statute “unless:”
(a) There is a substantial risk that he will not conform to the conditions of parole; (b) His release would depreciate the seriousness of his crime or promote disrespect for law; (c) His release would have a substantially adverse effect on institutional discipline; or (d) His continued correctional treatment, medical care, or vocational or other training in the facility will substantially enhance his capacity to lead a law-abiding life when released at a later date.
Neb.Rev.Stat. § 83-1,114(1) (1979) (cited in Greenholtz, 442 U.S. at 11, 99 S.Ct. at 2106). Similarly, in Evans v. Dillahunty, this court found that if certain criteria set forth in the federal parole statute were met, then the petitioner acquired a liberty interest. 662 F.2d at 526. That statute provides:
If an eligible prisoner has substantially observed the rules of the institution * * and if the Commission * * * determines:
(1) that release would not depreciate the seriousness of his offense or promote disrespect for the law; and
(2) that release would not jeopardize the public welfare; [then] subject to the * * guidelines promulgated by the Commission * * *, such prisoner shall be released.
18 U.S.C. § 4206(a) (1982) (emphasis added). These criteria not only placed substantive limitations on the officials’ discretion, but they directed that the prisoner be released upon satisfaction of certain criteria. See also Clark v. Brewer, 776 F.2d 226, 231 (8th Cir.1985) (policy statements permitting placement of prisoners in close management if their “continued presence in the general population poses a threat to life, property, self, staff, or other inmates, [or] to the security or orderly running of the institution, or [if there exists] the medical necessity for such segregation”); Parker, 750 F.2d at 658 (Arkansas regulation listing factors to take into account in determining suitability for parole).
We agree that the mandatory portions of the South Dakota parole regulations provide some limitations on the parole board’s discretion. See S.D.Admin.R. 17:60:02:01. They provide for a hearing, consideration of the inmate’s history, and consideration of treatment possibilities and plans for the inmate. However, these mandates are directed toward the factors the board must take into consideration, and do not mandate the inmate’s ultimate release. Even if the mandatory criteria are satisfied, the parole board maintains the ultimate discretionary authority to grant or deny the parole release. We conclude South Dakota’s regulations created no liberty interest in parole.8
*1283Accordingly, we hold that Dace had no protected liberty interest in his parole. The July 22, 1986, decision of this court is therefore vacated and the judgment of the district court is affirmed.
. The Honorable John B. Jones, United States District Court for the District of South Dakota, presiding.
. When Dace requested that the board provide an explanation for its decision, the Board responded that its policy was to refrain from giving reasons for denial of parole. Regardless of whether due process is required under the Constitution, the failure of a parole board to provide reasons for its denial of parole can be counterproductive, at least in some instances, to the state's interest. As stated by the Fourth Circuit in Franklin v. Shields, 569 F.2d 784 (4th Cir.1977), cert. denied, 435 U.S. 1003, 98 S.Ct. 1659, 56 L.Ed.2d 92 (1978):
In many instances, by furnishing the reasons for parole denial, the Board can instruct the prisoner about the changes that are expected of him if he is to meet the criteria for release. As the record reveals, however, there are some prisoners who are not considered fit for parole because of such a factor as a long history of recidivism. These prisoners are not in a position to remedy their deficiencies even if the Board states its reasons in writing. Nevertheless, a statement of reasons is important, for it will show that the Board has not acted arbitrarily.
569 F.2d at 797.
. See Olim v. Wakinekona, 461 U.S. 238, 103 S.Ct. 1741, 75 L.Ed.2d 813 (1983); Hewitt v. Helms, 459 U.S. 460, 103 S.Ct. 864, 74 L.Ed.2d 675 (1983); Connecticut Bd. of Pardons v. Dumschat, 452 U.S. 458, 101 S.Ct. 2460, 69 L.Ed.2d 158 (1981); Greenholtz, 442 U.S. 1, 99 S.Ct. 2100; Evans v. Dillahunty, 662 F.2d 522; Williams v. Missouri Bd. of Probations & Parole, 661 F.2d 697 (8th Cir.1981), cert. denied, 455 U.S. 993, 102 S.Ct. 1621, 71 L.Ed.2d 855 (1982).
. E.g., Greenholtz, 442 U.S. at 11, 99 S.Ct. at 2106; Williams v. Missouri, 661 F.2d 697, 698 (8th Cir.1981) (parole board "shall" release inmate "when” there is a reasonable probability that prisoner can be released without detriment to community or to himself).
. On July 1, 1985, a new parole statute became effective in South Dakota. It concludes: "Neither this section or its application may be the basis for establishing a constitutionally protected liberty, property or due process interest in any prisoner.” S.D. Codified Laws Ann. § 24-15-8 (Supp.1986).
. Cf. Nash, 781 F.2d at 668 (Missouri statutes providing that inmate "may" be transferred from one facility to another and that inmate “may” be furloughed confers no protected liberty interest in transfer or furlough); Gale, 763 F.2d at 343 (8th Cir. 1985) (amended Missouri parole statute providing that when parole board decides that prisoner can be released without detriment to community or himself, the board "may in its discretion” grant parole does not confer protected liberty interest on prisoner); Parker, 750 F.2d at 656-57 (no liberty interest in parole provided by Arkansas statute which states parole board "may” release inmate when he can be released without detriment to community or self); Irving v. Thigpen, 732 F.2d 1215, 1217 (5th Cir.1984) (Mississippi statute grants no liberty interest where prisoner "may" be released on parole if he meets substantive criteria); Williams v. Briscoe, 641 F.2d 274, 276 (5th Cir.), cert. denied, 454 U.S. 854, 102 S.Ct. 299, 70 L.Ed.2d 147 (1981) (no liberty interest under Texas statute stating board "may” recommend parole when certain criteria are satisfied); Wagner v. Gilligan, 609 F.2d 866, 867 (6th Cir.1979) (no liberty interest where Ohio board "may” grant parole if interests of justice and society’s welfare would be furthered).
. Rule 17:60:02:07 states:
The factors to be considered by the board in all hearings on application for parole may include, but shall not be limited to, the following:
(1) The inmate’s personal and family history;
(2) The inmate’s attitude, character, capabilities and habits;
(3) The nature and circumstances of the inmate’s offense;
(4) The number, nature and circumstances of the inmate’s prior offenses, if any;
(5) The successful completion or revocation of previous probation or parole granted to the inmate;
(6) The inmate’s conduct in the institution, including efforts directed toward self-improvement;
*1282(7) The inmate’s understanding of his own problems and his willingness to work towards overcoming them;
(8) The inmate’s total personality as it reflects on the possibility that he will lead a law-abiding life without harm to society;
(9) The inmate’s family and marital circumstances and the willingness of the family and others to help the inmate upon release on parole from the institution;
(10) The soundness of the parole program and whether it will promote the rehabilitation of the inmate;
(11) The inmate’s specific employment and/or plans for further formal education;
(12) The inmate’s plans for additional treatment and rehabilitation while on parole;
(13) The effect of the inmate’s release on the community;
(14) The effect of the inmate’s release on the administration of justice; and
(15) The effect of the inmate’s release on victims of crimes committed by the inmate.
S.D.Admin.R. 17:60:02:07 (1979).
. We feel compelled to respond briefly to the dissent of Judge Arnold. We do so, not for the sake of argument, but because of concerns that his analysis is likely to lead to more confusion in an already complex field of understanding. First, his basic disagreement with the Supreme Court as to the meaning of "liberty” fails to recognize, as in the definition of property, that state law regarding the parole of state prisoners *1283defines the meaning of liberty. See Greenholtz, 442 U.S. 1, 99 S.Ct. at 2101. His disagreement is with the Supreme Court not this court, which of course must adhere to the law set forth by the Supreme Court.
Second, his application of Greenholtz fails to recognize that before a liberty interest is established, in the factual context involved, the state must create "an expectancy of release.” The fact that particularized criteria must he considered by the Board as explained, does not create a situation of mandatory release. In that sense, the present case is clearly distinguishable from Greenholtz.
Finally, the dissent suggests a liberty interest may exist when a state prisoner is denied parole by exercising free speech. It indicates this sets forth an internal contradiction of constitutional principles. In all due respect, this simply is not so. First such an unusual factual hypothesis is clearly not germane to our discussion. The alleged internal contradiction is self-constructed. More importantly, it overlooks the well established principle that when first amendment interests are at issue under the fourteenth amendment, it is the first amendment right that is being vindicated through incorporation under the due process clause. Cf. Pickering v. Board of Educ., 391 U.S. 563, 88 S.Ct. 1731, 20 L.Ed.2d 811 (1968). As Judge Alvin Rubin has succinctly observed, although substantive due process may provide “a quantitative component” of the Bill of Rights, the "component is derived from the nature of the right violated, not from the due process clause.” Rubin, Deprived of Due Process: The Fourteenth Amendment and Abuse of Power, 16 N.M.L.Rev. 199, 212 (1986).