By a petition under our original jurisdiction,1 Ertle Dial, an inmate at Graterford SCI, challenges the constitutionality of the requirement that he submit a *3blood sample for DNA testing pursuant to the DNA Detection of Sexual and Violent Offenders Act (Act).2 This is an issue of first impression. Dial contends that the Act, by retroactively adding a condition of parole, violates the doctrine of separation of power, invalidates his guilty plea,3 and violates the ex post facto prohibitions of the constitutions of Pennsylvania and the United States and the fourth amendment of the United States Constitution. Dial avers that during his confinement at Gra-terford, following his entry of a guilty plea to an unspecified sex offense, a sample of his blood was taken for DNA testing pursuant to Section 306(b) of the Act, 35 P.S. § 7651.306(b). He seeks the removal of his DNA information from the data bank and an injunction against further DNA testing as a condition of his release on parole.
Respondents, Donald Vaughn, Superintendent at Graterford, the Commonwealth Attorney General and the State Police, (collectively referred to as Commonwealth) filed preliminary objections in the nature of demurrers to the claims that the Act violates the separation of powers doctrine and constitutes an ex post facto law. In deciding preliminary objections, we accept as true the well-pleaded facts that are material and relevant to petitioner’s claim. Dial v. Board of Probation and Parole, 706 A.2d 901, 902 (Pa.Cmwlth. 1998). We need not accept as true conclusions of law, unwarranted inferences from facts, argumentative allegations or expressions of opinion. Id.
In general, Pennsylvania’s DNA Act establishes an administrative process for the implementation of a DNA identification system as a tool in criminal investigations and for deterrence of recidivist crime. 35 P.S. §§ 7651.102 and 7651.302. The identification system contains DNA data from persons convicted of felony sex offenses, murder, harassment and stalking, and indecent assault. 35 P.S. § 7651.306. Section 306 of the Act establishes requirements for the submission of blood samples from persons convicted of the specified crimes. Section 306(b) provides as follows:
(b) Conviction before effective date.
- A person who has been convicted or adjudicated delinquent for a felony sex offense or other specified offense before the effective date of this section and who is still serving a term of confinement in connection therewith on the effective date of this section shall not be released in any manner prior to the expiration of his maximum term of confinement unless and until a DNA sample has been withdrawn.
The Commonwealth first demurs to Dial’s claim that the Act deprives him of eligibility for parole and in consequence affects the duration of his incarceration in violation of the doctrine of separation of powers. There is no question that final judgments of the judiciary are inviolable and a final judgment of sentence may not be disturbed by a subsequent legislative change. Commonwealth v. Sutley, 474 Pa. 256, 263, 378 A.2d 780, 784-785 (1977). This rule does not, however, preclude legislative enactment that changes the manner of executing the sentence. In Sutley, the court explained:
[T]he legal sentence is the maximum sentence. The reason being that while the minimum sentence determines parole eligibility, the maximum sets forth the period of time that the state intends to exercise its control over the offender for his errant behavior. The judicial *4discretion is the determination of the period of control over the person of the offender in view of the nature of the crime, the background of the defendant and the other pertinent considerations for such a decision. It is this exercise of discretion that the rule of the “inviolability of final judgment” seeks to protect. The institution in which the sentence is to be served, the objects sought to be accomplished during this period of control and all the other penological considerations are not primarily judicial functions.
Id. at 268, 378 A.2d at 786 (citations omitted).
The requirement that Dial submit to pre-release withdrawal of a blood sample for DNA testing does not alter his maximum sentence. Nor does the Act alter Dial’s parole eligibility date. Once eligibility has been achieved by incarceration for the prescribed minimum time, actual release on parole may depend on full compliance with a variety of prison rules and administrative requirements. The Act defines an administrative requirement that must be satisfied prior to release. This requirement is similar to the requirement for acquisition and storage of other convict identification records in the form of photos, fingerprints and physical description compiled at the time of arrest. See 18 Pa.C.S. § 9112 and the Act of April 27, 1927, P.L. 414, as amended, 61 P.S. §§ 2171-2177. The power to parole is an administrative function. Sutley, 474 Pa. at 266, 378 A.2d at 785 quoting Commonwealth ex rel. Banks v. Cain, 345 Pa. 581, 588-89, 28 A2d 897, 901 (1942). In the instant case, the Act establishes an administrative process for identification and Dial challenges the particular subsection that promotes prisoner cooperation with the identification process. No provision of the Act alters the judgment of sentence rendered by the sentencing court. For this reason, Dial is unable to maintain a claim that the Act violates the doctrine of separation of powers. Accordingly, the Commonwealth’s preliminary objection in the nature of a demurrer to this claim is sustained.
Next, the Commonwealth demurs to Dial’s claim that subsection 306(b) of the Act, 35 P.S. § 7651.306(b), effects an ex post facto enhancement of his sentence in violation of Article 1, Section 10 of the United States Constitution and Article 1, Section 17 of the Pennsylvania Constitution. A law transgresses the ex post facto prohibition only where, first, the law is retrospective and second, it alters the definition of criminal conduct or increases the penalty by which crime is punishable. California Dep’t of Corrections v. Morales, 514 U.S. 499, 115 S.Ct. 1597, 131 L.Ed.2d 588 (1995). See also Del Valle v. Workmen’s Compensation Appeal Bd. (Pennsylvania Dep’t of Educ.), 687 A.2d 1211, 1212 (Pa.Cmwlth.1997).4 There is no ex post facto violation if the legislation is not penal in nature, Van Doren v. Mazurkiewicz, 695 A.2d 967 (Pa.Cmwlth.1997); Commonwealth v. Kline, 695 A.2d 872 (Pa.Super.1997), alloc. denied, 552 Pa. 694, 716 A.2d 1248 (1998), but is merely procedural, U.S. v. Askari, 608 F.Supp. 1045, 1048 (E.D.Pa.1985).
The Commonwealth argues that the blood testing requirement is not penal and *5therefore cannot offend the ex post facto clause. We agree. The testing program is non-penal because there is no evidence, in its purpose or its design, of any intent to punish or requirements so harsh ■ as to objectively constitute punishment. E.B. v. Vemiero, 119 F.3d 1077, 1088-89 (3d Cir. 1996), cert. denied, - U.S. -, 118 S.Ct. 1039, 140 L.Ed.2d 105 (1998). The collection of blood for identification and establishment of a DNA data bank is, like fingerprinting and photographing, a non-penal, administrative requirement. See Gilbert v. Peters, 55 F.3d 237, 239 (7th Cir.1995). See also Rise v. Oregon, 59 F.3d 1556, 1562 (9th Cir.1995), cert. denied, 517 U.S. 1160, 116 S.Ct. 1554, 134 L.Ed.2d 656 (1996); Kruger v. Erickson, 875 F.Supp. 583, 589 (D.Minn.1995), affirmed, 77 F.3d 1071 (8th Cir.1996). Moreover, the blood testing is reasonable because it constitutes a limited search involving minor intrusion, Skinner v. Railway Labor Executives’ Ass’n, 489 U.S. 602, 625, 109 S.Ct. 1402, 103 L.Ed.2d 639 (1989), on persons with diminished expectations of privacy, Bell v. Wolfish, 441 U.S. 520, 559-60, 99 S.Ct. 1861, 60 L.Ed.2d 447 (1979), for the purpose of improved law enforcement, Jones v. Murray, 962 F.2d at 307.
Nor do we believe that denial of parole for refusal to comply with the Act’s sample collection requirements is ex post facto. We are guided in this decision by the opinion of the United States Court of Appeals for the Fourth Circuit in Jones v. Murray, 962 F.2d 302 (4th Cir.), cert. denied, 506 U.S. 977, 113 S.Ct. 472, 121 L.Ed.2d 378 (1992).5 In 1990, the Commonwealth of Virginia enacted a DNA de tection act similar to the Pennsylvania statute.6 Pursuant to the statute, the Virginia Department of Corrections established procedures by which blood samples would be drawn from inmates falling within the scope of the statute. The department required every felon in custody on or after the relevant date to provide a blood sample prior to the individuals’ discretionary parole eligibility date or thirty days prior to the mandatory parole date if the discretionary date had passed. Six inmates challenged the statute and regulations on the grounds that the program violated the fourth amendment, the ex post facto clause and the fourteenth amendment due process clause.
With respect to the ex post facto claim, the court in Jones held that the prohibition against the release of non-eompliant inmates who had reached their mandatory parole date7 was an ex post facto enhance*6ment of the terms of original sentence. However, section 306 of the Pennsylvania Act does not limit release beyond the mandatory release date established under the terms of the original sentence. Thus, the Pennsylvania Act does not increase the measure of punishment attached to the crime at the time of its commission and thereby avoids the constitutional defect in the Virginia statute.
Where the mandatory parole date had not yet been reached, the Jones court concluded that retention of non-compliant inmates was not an ex post facto law since that retention did not exceed the terms of the prisoners’ original sentence. The court reasoned that prisoners who refused to provide a blood sample for DNA testing could be administratively punished and such punishment would not be ex post facto. The court stated:
The Ex Post Facto Clause does not prevent prison administrators from adopting and enforcing reasonable regulations that are consistent with good prison administration, safety and efficiency....
[C]hanges in a prisoner’s location, variations of daily routine, changes in conditions of confinement (including administrative segregation), and denials of privileges - matters which every prisoner can anticipate are contemplated by his original sentence to prison - are necessarily functions of prison management that must be left to the broad discretion of prison administrators.
It is precisely because reasonable prison regulations, and subsequent punishment for infractions thereof, are contemplated as part of the sentence of every prisoner, that they do not constitute additional punishment and are not classified as ex post facto. Moreover, since a prisoner’s original sentence does not embrace a right to one set of regulations over another, reasonable amendments, too, fall within the anticipated sentence of every inmate. We therefore conclude that neither [the] blood-testing requirement, itself, nor the infliction of punishment within the terms of the prisoner’s original sentence for a violation of the requirement, is ex post facto, (citations omitted).
Jones v. Murray, 962 F.2d at 309. Accord Doe v. Gainer, 162 Ill.2d 15, 204 Ill.Dec. 652, 642 N.E.2d 114 (1994), ceri. denied, 513 U.S. 1168, 115 S.Ct. 1139, 130 L.Ed.2d 1099 (1995). Additionally, the court noted that “whatever punishment or disadvantage is imposed results, not by reason of conduct that took place before enactment of the statute, so as to become retrospective, but from conduct that occurred after enactment in refusing to comply with reasonable regulation.” Id. at 309, n. 3. Accord Gilbert v. Peters, 55 F.3d at 239. Like that portion of the Virginia statute found to pass constitutional muster in Jones v. Murray, the Pennsylvania DNA Act imposes an administrative punishment for non-compliance with a reasonable administrative regulation enacted prior to the act of non-compliance.
Finally, in his petition, Dial asserts that the testing program under the DNA Act violates the Fourth Amendment prohibition against unreasonable search and seizure. The Commonwealth, has not asserted a preliminary objection to this claim. However, our determination that the Act is a valid administrative regulation is dependent upon our conclusion that the Act passes fourth amendment scrutiny.
Without question, obtaining a blood sample for testing is a search and seizure subject to the reasonableness requirement established under the fourth amendment. Schmerber v. California, 384 U.S. 757, 767, 86 S.Ct. 1826, 16 L.Ed.2d 908 (1966). In some limited situations, special needs beyond the normal law enforcement needs may make the warrant and probable cause requirement impracticable and permit a determination of fourth amendment reasonableness based upon a balancing of governmental and privacy interests. Griffin v. Wisconsin, 483 U.S. *7868, 873, 107 S.Ct. 3164, 97 L.Ed.2d 709 (1987). In the context of Dial’s situation as a convicted inmate, the reasonableness of the search may be established even absent a showing of probable cause or reasonable suspicion. Bell v. Wolfish, 441 U.S. at 559, 99 S.Ct. 1861. The court, in Bell v. Wolfish, stated that in deciding the reasonableness of an inmate search, “Courts must consider the scope of the particular intrusion, the manner in which it is conducted, the justification for initiating it, and the place in which it is conducted.” Id. at 559, 99 S.Ct. 1861.
In the instant case, the blood-testing program subjects a target population of convicted inmates with reduced privacy expectations, Bell, 441 U.S. at 559-60, 99 S.Ct. 1861, to a relatively minimal intrusion, Skinner, 489 U.S. at 625, 109 S.Ct. 1402; Schmerber, 384 U.S. at 771, 86 S.Ct. 1826, in furtherance of the Commonwealth’s need to maintain an identification system to deter recidivism. The slight intrusion occasioned by the withdrawal of blood is outweighed by the special public interest in maintaining an identification data bank. See Rise v. Oregon, 59 F.3d 1556, 1560 (holding Oregon statute creating DNA database not in violation of Fourth Amendment and citing Brown v. Texas, 443 U.S. 47, 50-51, 99 S.Ct. 2637, 61 L.Ed.2d 357 (1979) for application of “special needs” balancing test) and Jones v. Murray, 962 F.2d at 306 (applying “special needs” balancing test to determine that sample collection program under Virginia DNA identification statute was reasonable). The program established by the Act is, on its face, evenhanded in its application and reasonable in the manner in which it is conducted. Petitioner has not made any averments tending to demonstrate otherwise.
Accordingly, the preliminary objections to the amended petition for review are sustained. In light of our conclusion that, as a matter of law, the petitioner is unable to prevail on any theory espoused in his amended petition, the amended petition is dismissed.
ORDER
AND NOW, this 20th day of May, 1999, the preliminary objections to the amended petition for review are hereby sustained and the petition is hereby dismissed for failure to state a claim upon which relief may be granted.
. Dial’s amended petition for a writ of habeas corpus has been treated as a petition for review.
. Act of May 28, 1995, P.L. 1009, §§ 101-1102, 35 P.S. §§ 7651.101-7651.1102.
. The instant petition for injunctive and declaratory relief challenging the constitutionality of the DNA Act is not the proper forum in which to collaterally attack the validity of the plea. The proper procedure for attacking a guilty plea following sentencing is to file with the trial court, which accepted the plea, a petition to withdraw the plea. Commonwealth v. Porta, 297 Pa.Super. 298, 443 A.2d 845, 847 (1982) or a petition for post conviction relief pursuant to 42 Pa.C.S. §§ 9541-9546.
. In Del Valle, our court, in articulating the elements of an ex post facto law, cited Crowell v. U.S. Parole Commission, 724 F.2d 1406 (3d Cir.1984) for the premise that a law is ex post facto if it operates retroactively and results in new disadvantage to the offender. After the Supreme Court’s decision in Collins v. Youngblood, 497 U.S. 37, 110 S.Ct. 2715, 111 L.Ed.2d 30 (1990), the inquiry became more focused and required a determination of whether the definition of the crime changed or the penalty was enhanced. See California Dep’t of Corrections v. Morales, 514 U.S. 499, 506 n. 3, 115 S.Ct. 1597, 131 L.Ed.2d 588 (1995). We believe the focus on specifics rather than vague disadvantage is the better approach and, therefore, clarify that the "disadvantage” referred to in Del Valle is the alteration in the definition of crime or increase in punishment. See Lynce v. Mathis, 519 U.S. 433, 441, 117 S.Ct. 891, 137 L.Ed.2d 63 (1997).
. DNA identification statutes have also withstood constitutional scrutiny in the Ninth Circuit, Rise v. Oregon, 59 F.3d 1556 (9th Cir.1995), cert. denied, 517 U.S. 1160, 116 S.Ct. 1554, 134 L.Ed.2d 656 (1996) (holding Oregon statute not in violation of Fourth Amendment or Ex Post Facto Clause), and in the Tenth Circuit, Boling v. Romer, 101 F.3d 1336 (10th Cir.1996) (holding Colorado statute not in violation of Fourth Amendment, Fifth Amendment or due process interests); Schlicher v. Peters, 103 F.3d 940 (10th Cir.1996) (holding Kansas statute not in violation of Fourth Amendment).
. See Va.Code. §§ 19.2-310.2 through 19.2-310.7. Section 19.2-310.2 provided in pertinent part, as follows:
After July 1, 1990, the blood sample shall be taken prior to release from custody.
Notwithstanding the provisions of 53.1— 159, [the mandatory release on parole requirement], any person convicted of a felony who is in custody after July 1, 1990, shall provide a blood sample prior to his release.
.At the time Virginia enacted its DNA blood testing program, Va.Code §§ 19.2-310.2-19.2-310.7, there existed a mandatory parole system pursuant to Va.Code § 53.1-159 which provided as follows:
Every person who is sentenced and committed under the laws of the Commonwealth to the Department of Corrections ... shall be released on parole by the Virginia Parole Board six months prior to his date of final discharge.
Pennsylvania has not enacted a mandatory parole statute and parole in Pennsylvania is discretionary. Weaver v. Pennsylvania Bd. of Probation and Parole, 688 A.2d 766 (Pa.Cmwlth.1997); Reider v. Pennsylvania Bd. of Probation and Parole, 100 Pa.Cmwlth. 333, 514 A.2d 967 (1986).