OPINION
By the Court,
Zenoff, J.:This appeal is taken by the State from an order entered by the district court granting post-conviction relief correcting respondent’s sentence to a term of one year and three months from an original sentence of four years for the unlawful sale of narcotics.
At the time sentence was first pronounced against the appellant the district judge had before him a memorandum from the chief parole and probation officer of the board of parole commissioners, which he interpreted to suggest that most inmates need supervision and guidance when released from prison, that such service could not be rendered to prisoners serving out short sentences but could be rendered to prisoners who were serving sentences up to six years and who would be eligible for parole for actually serving, in a successful manner, one year or less at the state prison.
The trial judge, believing that parole would very likely be granted after one year if appellant served that year in an exemplary manner, pronounced a four-year sentence.
After serving one year appellant was denied parole. He then petitioned the district court for post-conviction relief pursuant to NRS 177.315 et seq., and the matter came before the district judge who had imposed the original sentence. During the course of the post-conviction hearing the district judge learned that while incarcerated appellant had conducted himself in an exemplary manner and had been given recommendation for parole by the prison authorities.
*146Relying upon United States v. Myers, 374 F.2d 707, 710 (3rd Cir. 1967), and other cases of similar stature, the district judge changed the sentence from four years to one year, three months, nunc pro tunc, and said: “[I] am correcting it because this Court considered a decision of policy which apparently is not a policy considered by the parole commissioners. And had this Court been aware that this would have been the fact, it would not have imposed the sentence of 4 years in the Nevada State Prison.”
The State urges that the determination of the trial court constitutes an unlawful invasion into one of the functions of the legislative branches of the government and therefore is invalid.
1. This court ruled in Warden v. Peters, 83 Nev. 298, 429 P.2d 549 (1967), that when a trial court errs in rendering a judgment and that mistake is one of fact, the trial court can correct its own mistake. Some errors are clerical, for instance, the insertion of a wrong date allowing nunc pro tunc correction; or the imposition of a sentence not provided-by statute, such as in Peters, supra, who was sentenced for a completed crime instead of an attempt to commit the crime. The incorrect sentence was modified to impose the penalty for the attempt to commit that crime. Compelling a defendant to serve a period of incarceration longer than the penalty provided is manifestly unfair and constitutionally infirm.
Nowhere, however, does the parole department bulletin, relied upon by the trial court, guarantee the amount of time to be served. The experienced trial judge knew that after sentencing the matter of parole is in the hands of the parole board subject to the rules and discretion of that body. The court was aware that Clark was subject to the board’s function of review in stating that if Clark conducted himself as a good inmate and had the recommendation of the prison authorities that very likely he would be paroled after the term of one year. The term “very likely” shows that court’s awareness that Clark’s release was subject to the parole board’s approval. Despite the favorable recommendation of the prison authorities the board’s refusal was based on solid reasons which included Clark’s past record for the same or similar offense for which he was convicted and now serving time.
2. If the judge was of the opinion at the time of sentencing that Clark should spend only one year in prison, he did not so state in the record nor did he communicate his suggestion to the parole board as is sometimes done. Such a recommendation while not binding might have been of assistance in the board’s consideration of the case.
*147Nevertheless, the sentence when imposed was statutorily proper. Now by subsequent action a trial court cannot do indirectly what we stated in State v. District Court, 85 Nev. 485, 457 P.2d 217 (1969), cannot be done directly. This action violates the intent and purpose of parole statutes and constitutes an invasion of the legislative and executive functions of government. State v. District Court, supra, p. 488. In this State the granting of relief from incarceration is authorized by the legislature and performed by the state board as an executive function. NRS 213.1099; NRS 213.110; NRS 213.120.
If, of course, an inequity can be shown, it is possible that Clark can seek immediate relief before the State Board of Pardons Commissioners. (NRS 213.010; NRS 213.100.) That constitutional body is distinctive and separate from the parole department.
Reversed.
Thompson, C. J., and Gunderson, J., concur,