Concurring and Dissenting Opinion by
Mr. Justice Nix:There can be no serious question that a sentence once imposed may not be altered, modified or amended, even though within the statutory period of thirty days1 where the effect of such modification, alteration or amendment constitutes a violation of the double jeopardy clauses of the federal and state constitutions. My difference arises from the belief that this principle of law has no applicability to the facts of the instant appeal. In my view the distinguishing factor here is that the 8% to 10 year sentence was in direct contravention of the Act of September 26, 1951, P. L. 1460, § 1, 19 P.S. § 1057.2
*281The power to define criminal conduct and to assign the sanction to be imposed is a prerogative of the legislature and not the judicial branch of government. Furthermore, the legislature may delegate the implementation of that power to the courts and proscribe limitations in the exercise of the power under the grant. Commonwealth v. Sweeney, 281 Pa. 550, 127 A. 266 (1924); Commonwealth v. Kalck, 239 Pa. 533, 87 A. 61 (1913); Commonwealth ex rel. Bates v. McKenty, 52 Pa. Superior Ct. 332 (1913). The Act of 1951 directs that a sentence which seeks to commit a male offender to a State Penitentiary must contain a maximum and minimum sentence. With equal force the provision requires that the maximum not exceed the maximum punishment set by the legislature for the crime charged and that the minimum not exceed one half of the maximum imposed by the court. Non-compliance with the express directions of the act conferring the power to sentence can only result in an ineffective and futile attempt to exercise that power.
That we have held that it is the maximum term which has legal effect as the sentence, Commonwealth v. Daniels, 430 Pa. 642, 243 A.2d 400 (1968); Commonwealth ex rel. Carmelo v. Smith, 347 Pa. 495, 32 A.2d 913 (1943); Commonwealth v. Kalck, supra, and Commonwealth ex rel. Bates v. McKenty, supra, does not alter the conclusion. The failure in this case was to impose a proper minimum, but although the mini*282mum is not the legal portion of the sentence, the gravaman of the error is that the power was employed in a manner in direct violation to the express terms of the grant. Thus, in my judgment, it is immaterial as to what portion of the sentence the error relates, if it results from a failure to comply with the express provisions of the Act of 1951 an efficacious sentence cannot he imposed.
The reasoning of the United States Supreme Court in Bozza v. United States, 330 U.S. 160 (1947) is pertinent. There the trial judge sentenced appellant Bozza to a simple term of imprisonment in violation of the statute which required as a minimum mandatory penalty both a fine and term of imprisonment. Five hours later the judge recalled Bozza and imposed a $100 fine in addition to the original imprisonment sentence. In upholding this action the Supreme Court stated: “If this inadvertent error cannot be corrected in the manner used here by the trial court, no valid and enforceable sentence can be imposed at all. Cf. Jordan v. United States, 60 F.2d 4, 6, with Barrow v. United States, 54 App. D.C. 128, 295 F. 949. This Court has rejected the ‘doctrine that a prisoner, whose guilt is established, by a regular verdict, is to escape punishment altogether, because the court committed an error in passing the sentence.’ In re Bonner, supra at 260. The Constitution does not require that sentencing should be a game in which a wrong move by the judge means immunity for the prisoner. See King v. United States, 69 App. D.C. 10, 15, 98 F.2d 291, 296. In this case the court ‘only set aside what it had no authority to do and substitute [d] directions required by the law to be done upon the conviction of the offender.’ In re Bonner, supra at 260. It did not twice put petitioner in jeopardy for the same offense. The sentence, as corrected, imposes a valid punishment for an offense instead of an invalid punishment for that offense.” 330 U.S. at 166-167. (Footnote omitted.)
*283This reasoning is not contradictory to that espoused by our Court in prior cases. Commonwealth v. Allen, 443 Pa. 96, 277 A.2d 803 (1971) and Commonwealth v. Silverman, 442 Pa. 211, 275 A.2d 308 (1971), relied upon by the majority, concerned judicial power to increase sentences which were legal in the first instance. Indeed, the Bozza case was distinguished in Allen on the ground that the original sentence was illegal.
I agree that the subsequent sentence of 8% to 20 years must be vacated but I so conclude because of the Court’s attempt to enter this sentence in the appellant’s absence. I would vacate and remand with the instruction that the erroneously entered sentence does not limit or restrict in any manner, the Court’s power to impose a new sentence.
Act of June 1, 1959, P. L. 342, § 1, 12 P.S. § 1032 (Supp. 1973-74).
The statute states in pertinent part: “Whenever any person, convicted in any court of this Commonwealth of any crime punishable by imprisonment in a State penitentiary, shall be sentenced *281to imprisonment therefor in any penitentiary or other institution of this State, or in any county or municipal institution, the court, instead of pronouncing upon such convict a definite or fixed term of imprisonment, shall pronounce upon such convict a sentence of imprisonment for an indefinite term: Stating in such sentence the minimum and maximum limits thereof; and the mawimum limit shall never eweeed the mawimum time now or hereafter prescribed as a penalty for such offense; and the minimum limit shall never eweeed one-half of the mawimum sentence prescribed by any court.” (Emphasis added.)