(1) Post-conviction relief pursuant to ORS 138.510 to 138.680 shall be granted by the court when one or more of the following grounds is established by the petitioner:
(a) A substantial denial in the proceedings resulting in petitioner’s conviction, or in the appellate review thereof, of petitioner’s rights under the Constitution of the United States, or under the Constitution of the State of Oregon, or both, and which denial rendered the conviction void.
(b) Lack of jurisdiction of the court to impose the judgment rendered upon petitioner’s conviction.
(c) Sentence in excess of, or otherwise not in accordance with, the sentence authorized by law for the crime of which petitioner was convicted; or unconstitutionality of such sentence.
(d) Unconstitutionality of the statute making criminal the acts for which petitioner was convicted.
(2) Whenever a person petitions for relief under ORS 138.510 to 138.680, ORS 138.510 to 138.680 shall not be construed to deny relief where such relief would have been available prior to May 26, 1959, under the writ of habeas corpus, nor shall it be construed to affect any powers of executive clemency or pardon provided by law.
(3) ORS 138.510 to 138.680 shall not be construed to limit the original jurisdiction of the Supreme Court in habeas corpus as provided in the Constitution of this state.