dissenting.
Notwithstanding the axiom that a conviction based on a defendant’s plea is either constitutionally valid or invalid, the majority’s opinion is somewhat a judicial shell game which requires a defendant to locate the procedural pellet for challenging the constitutionality of the defendant’s prior plea-based conviction. Fundamental unfairness occurs, however, because there is no pellet to be uncovered.
The majority notes the statement in Gonzales v. Grammer, 848 F.2d 894, 896 n.3 (8th Cir. 1988): “A state is at liberty to set up whatever procedural requirements it deems necessary for processing challenges to prior convictions in a habitual criminal proceeding.” From the preceding Gonzales excerpt, one may infer that, although a state’s legislature or judiciary may fashion a particular procedure for a defendant’s challenge to the constitutionality of a prior plea-based conviction used for an enhanced penalty, the state, nonetheless, is constitutionally obligated to have a method or means by which a defendant can litigate the constitutional validity of the prior plea-based conviction used for enhancement purposes. Whatever procedure a state provides, the procedure shall not infringe a constitutional guarantee. Thus, while a specific procedure to challenge the constitutionality of a prior guilty or no-contest plea rests within the state’s discretion, a defendant’s right to challenge a prior and constitutionally invalid plea is not a matter of the state’s discretionary and procedural largess, but is a matter of due process which must be accorded a defendant who is subjected to a potential penalty or punishment through the criminal justice system. Nevertheless, from a launching pad of the federal footnote in Gonzales, the majority rockets to the *876conclusion that constitutional validity of a defendant’s prior plea-based conviction “may only be raised in a direct appeal or in a separate proceeding commenced for the express purpose of setting aside the judgment alleged to be invalid.” The logical response is: What is the “separate proceeding” available to set aside the prior plea-based conviction?
While it may be an expression of the all-too-obvious, the majority does not judicially fashion a separate proceeding for a defendant’s constitutional challenge to a prior plea-based conviction which is used for enhancement purposes. Rather, apart from mentioning a statutorily authorized direct appeal to test the constitutional validity of a conviction, the majority tacitly turns to the Legislature and Nebraska’s statutes for a procedure enabling a defendant to question the constitutional validity of a prior plea-based conviction. Are there any Nebraska statutory proceedings for evaluation and resolution of a defendant’s constitutional challenge to a prior plea-based conviction?
Is the majority alluding to a habeas corpus proceeding as the “separate proceeding commenced for the express purpose of setting aside” a defendant’s previous conviction? According to Neb. Rev. Stat. § 29-2801 (Reissue 1985), an applicant or petitioner for a writ of habeas corpus must be a person who “is or shall be confined in any jail of this state, or [who] shall be unlawfully deprived of his or her liberty . . . .” To entitle the applicant-petitioner to a writ of habeas corpus, “there must be an actual confinement or the present means of enforcing it.” Spring v. Dahlman, 34 Neb. 692, 693, 52 N.W. 567 (1892). The writ of habeas corpus, therefore, is unavailable to attack the constitutional validity of a defendant’s prior plea-based conviction unless the defendant is incarcerated as the result of that prior conviction. The likelihood of a defendant’s being incarcerated on account of a prior plea-based conviction, when a current prosecution involves an enhanced penalty based on such prior conviction, is mind-boggling, especially in cases of misdemeanor convictions. It is more probable, perhaps to the point of certainty, that a defendant, presently prosecuted, will have already served the sentence imposed as the result of the prior plea-based conviction, thereby disqualifying a previously *877convicted defendant as an applicant-petitioner for a writ of habeas corpus.
Is the “separate proceeding,” mentioned by the majority, a proceeding brought under the postconviction act, Neb. Rev. Stat. §§ 29-3001 et seq. (Reissue 1985)? Section 29-3001 provides that “[a] prisoner in custody under sentence . . . may file a verified motion [for postconviction relief].” In State v. Moore, 190 Neb. 271, 272, 207 N.W.2d 518, 519 (1973), this court stated: “The Post Conviction Act extends relief only to persons ‘in custody.’ ” Consequently, a defendant who has served a sentence imposed as the result of a plea-based conviction to be constitutionally challenged, or who is not incarcerated on account of such conviction, is not entitled to request postconviction relief.
Perhaps the suggested “separate proceeding” is a motion for new trial pursuant to Neb. Rev. Stat. § 29-2101 (Reissue 1985). However, except in the case of newly discovered evidence, a motion for new trial must be filed within 10 days after verdict unless the defendant is “unavoidably prevented” from filing the motion. See Neb. Rev. Stat. § 29-2103 (Reissue 1985). In any event, as prescribed by § 29-2103, a motion for new trial “must be filed within three years after the date of such verdict.” In virtually all cases, a defendant would be unable to utilize a motion for new trial to challenge a constitutionally invalid guilty or no-contest plea in reference to an enhancement proceeding because lapse of the specified time will have prevented opportunely filing the motion for new trial.
Maybe the majority is implying that a declaratory judgment action, authorized by Neb. Rev. Stat. §§ 25-21,149 et seq. (Reissue 1985), is the “separate proceeding” available to contest the constitutional validity of a prior plea-based conviction. Putting aside prodigious problems involving the statute of limitations, determination of necessary parties for the proceedings, and identification of a proper forum for the declaratory judgment action, assume that a defendant obtains a declaratory judgment that the plea on which the defendant’s prior conviction is based was unconstitutionally obtained. What effect does the declaratory judgment have? The declaratory judgment would not operate to set aside the *878previous plea-based conviction lest the declaring court act as an appellate court, reviewing and vacating another court’s judgment in the absence of authority for appellate action. A declaratory judgment action is not a substitute for a new trial or appeal; a method of destroying proper exercise of power in a former action; authority for a second trial by the same parties on identical issues in different forums; or a justification for an unnecessary decision; and does not approve collateral attacks on former adjudications or operate to supersede former adjudications or proper proceedings already pending in court. See, Moore v. Black, 220 Neb. 122, 368 N.W.2d 488 (1985); Zarybnicky v. County of Gage, 196 Neb. 210, 241 N.W.2d 834 (1976); Phelps County v. City of Holdrege, 133 Neb. 139, 274 N.W. 483 (1937). Consequently, a defendant, having obtained a declaratory judgment that the defendant’s prior plea was constitutionally invalid, would have to take the declaratory judgment to the court which accepted the plea in question. To what avail? One need not travel to the far boundaries of imagination to envision a judge’s response on presentation of a judgment, entered by another court at the trial level, declaring the judge’s prior convictional action void due to some judicial deficiency concerning a defendant’s constitutional rights.
Additionally, in Moore v. Black, supra, we considered the absence of any procedure for appellate review of a judgment and stated:
We have held that where no other method of appeal is provided, one may obtain judicial review by proceedings in error under [Neb. Rev. Stat. §§ 25-1901 et seq. (Reissue 1985). Citations omitted.] However, as in all appeals, the time requirements are mandatory and must be met in order for the appellate tribunal to acquire jurisdiction of the subject matter....
[Neb. Rev. Stat. § 25-1931 (Reissue 1985)] provides: “No proceedings for reversing, vacating, or modifying judgments or final orders shall be commenced unless within one calendar month after the rendition of the judgment or making of the final order complained of. . .
220 Neb. at 124-25, 368 N.W.2d at 490. Even the catchall error *879proceedings will undoubtedly be unavailable for a defendant’s challenge to a prior plea-based conviction.
It is indeed difficult, if not impossible, to elaborate all the questions and problems spawned in the majority’s nondescript “separate proceeding,” which, in the Churchillian characterization, is a “riddle wrapped in a mystery inside an enigma.” The fact remains that, unless a defendant is incarcerated or has timely filed a motion for new trial, there is no Nebraska procedure, judicially fashioned or statutorily authorized, to accommodate a defendant’s constitutional challenge to a prior plea-based conviction utilized for an enhanced penalty.
As expressed by the U.S. Supreme Court in Boykin v. Alabama, 395 U.S. 238, 243 n.5, 89 S. Ct. 1709, 23 L. Ed. 2d 274 (1969), regarding a guilty plea:
“A defendant who enters such a plea simultaneously waives several constitutional rights, including his privilege against compulsory self-incrimination, his right to trial by jury, and his right to confront his accusers. For this waiver to be valid under the Due Process Clause, it must be ‘an intentional relinquishment or abandonment of a known right or privilege.’ Johnson v. Zerbst, 304 U.S. 458, 464 [58 S. Ct. 1019, 82 L. Ed. 1461] (1938). Consequently, if a defendant’s guilty plea is not equally voluntary and knowing, it has been obtained in violation of due process and is therefore void. . . .” [Quoting from McCarthy v. United States, 394 U.S. 459, 89 S. Ct. 1166, 22 L. Ed. 2d 418(1969).]
Thus, according to Boykin, a defendant’s guilty plea which is not equally voluntary and knowing violates due process and is, therefore, void and a nullity. To paraphrase a well-known observation, void is void is void is void. Unless a defendant’s direct appeal challenges a constitutionally invalid plea, the majority of this court permits the State to use a defendant’s constitutionally invalid plea again and again for enhancement purposes. Cf. Burgett v. Texas, 389 U.S. 109, 115, 88 S. Ct. 258, 19 L. Ed. 2d 319 (1967): “[S]ince the defect in the prior conviction was denial of the right to counsel, the accused in effect suffers anew from the deprivation of that Sixth *880Amendment right.” However, a challenge to a prior plea-based conviction, proposed to be used for sentence enhancement, is not restricted to the ground that the prior conviction was obtained in violation of a defendant’s right to counsel, but may be based on violations of other constitutional rights, such as the rights mentioned in Boykin, namely, the rights to trial by jury, to remain silent, and to confront accusers. See People v. Sumstine, 36 Cal. 3d 909, 687 P.2d 904, 206 Cal. Rptr. 707 (1984). As a matter of due process required by the Nebraska and U.S. Constitutions, a prior plea-based conviction obtained in violation or denial of a constitutional right accorded an accused cannot be used in a subsequent criminal proceeding to establish the accused’s guilt or support an enhanced punishment. See Watkins v. People, 655 P.2d 834 (Colo. 1983).
Correctly analyzed, the question raised in Oliver’s case does not relate to a separate or collateral proceeding to set aside a prior conviction. Oliver’s case involves what basically is an evidential principle based on, and demanded by, due process, namely, a challenge to the present use of a constitutionally invalid plea at a present sentence hearing. In an enhancement proceeding, a defendant’s successful constitutional challenge to the validity of a prior plea-based conviction does not overturn the prior conviction, but results in exclusion or foreclosure of the prior plea-based conviction for the purpose of an enhanced penalty. See State v. Holsworth, 93 Wash. 2d 148, 607 P.2d 845 (1980). Therefore, challenging a prior plea-based conviction in a proceeding for an enhanced penalty is not a collateral attack to set aside the prior conviction alleged to be constitutionally invalid.
Further, in reference to prospective imposition of an enhanced penalty, the requirement of a separate proceeding to set aside a prior conviction based on a constitutionally invalid plea frustrates judicial economy and defeats efficient judicial administration in the criminal justice system. As a practicable procedure, the determination whether a defendant has previously entered a constitutionally valid guilty or no-contest plea, resulting in a conviction subsequently available for an enhanced penalty, should be a matter for the court in which the enhanced penalty is sought. This procedure would promote *881judicial economy as well as furnish fundamental fairness necessary for due process. The constitutional right of due process is much too precious to languish in a legal labyrinth. In accordance with due process required in the criminal justice system, Oliver must be permitted to question the constitutional validity of his prior plea-based convictions used for imposition of an enhanced penalty. As a prerequisite for imposition of any enhanced penalty, the State has, and must satisfy, the burden to prove the constitutional validity of every prior plea-based conviction in the basis for an enhanced penalty. See Watkins v. People, supra. To that end, the sentence imposed on Oliver should be set aside, and these proceedings should be remanded for a sentence hearing at which Oliver may challenge the constitutional validity of every prior plea-based conviction in the basis for an enhanced penalty. As the result of the sentence hearing on remand, the appropriate sentence should be imposed on Oliver.