OPINION
Judith Neely was found guilty but mentally ill on one count of first-degree murder, three counts of attempted murder, and two counts of aggravated battery. The trial court entered judgment and sentenced Neely to life imprisonment for the first-degree murder plus twenty-seven years for the other charges. The court ordered the sentences to run consecutively. On her first appeal to this Court, Neely challenged the statutes authorizing the guilty but mentally ill verdict (NMSA 1978, §§ 81-9-3 and -4 (Repl. Pamp.1984)). This Court upheld the statutory scheme and affirmed her convictions. State v. Neely, 112 N.M. 702, 709, 819 P.2d 249, 256 (1991) (Neely I). After this Court’s opinion was filed, the Clerk of the Supreme Court issued a mandate to the district court stating that the ease was remanded to the district court for “such further proceedings therein as may be proper, if any, consistent and in conformity with said Opinion and said Judgment.” Neely then filed a motion asking the district court to reconsider the sentence it had imposed. In her motion, she did not ask the court to change the length of her sentence, but asked the court to sentence her to an appropriate mental facility where she could receive treatment for her mental illness. The trial court denied the motion, stating that it had no discretion to consider a sentence less than that prescribed by statute when the verdict was guilty but mentally ill.
On this appeal, Neely challenges the trial court’s denial of her motion to modify her sentence. The State attempts to frame her argument as a challenge to the legality of the life sentence. We, however, construe her argument to be that the court’s denial of her motion was improper because the court had discretion to modify the original sentence. We believe that the trial court does not have discretion to modify a mandatory life sentence. Thus, we affirm.
The trial court had subject-matter jurisdiction to hear the motion. Before we turn to the main issue, we first must address the State’s contention that the trial court did not have subject-matter jurisdiction to hear Neely’s motion. The mandate in Neely I was issued October 10, 1991, and Neely filed her motion to reconsider her sentence on November 7. In her motion, she asserted jurisdiction in the trial court under NMSA 1978, Section 39-1-1 (Repl.Pamp.1991) (trial court has jurisdiction for thirty days after entry of judgment and for such further time as may be necessary to pass on motion directed to the judgment and filed within such period). The State argues that Section 39-1-1 has been construed as applying only to bench trials, and, because this case was decided by a jury, it is not applicable. In support of its proposition that Section 39-1-1 does not apply, the State cites Scofield v. J.W. Jones Construction Co., 64 N.M. 319, 324, 328 P.2d 389, 392 (1958), and State v. Padilla, 92 N.M. 19, 21, 582 P.2d 396, 398 (Ct.App.), cert. denied, 92 N.M. 180, 585 P.2d 324 (1978). But see State v. Peppers, 110 N.M. 393, 397, 796 P.2d 614, 618 (Ct.App.) (stating that a criminal defendant may challenge sentences under Section 39-1-1 so long as the procedure is in accordance with SCRA 1986, 5-614 and 5-801), cert. denied, 110 N.M. 260, 794 P.2d 734 (1990).1
The State correctly cites Scofield and Padilla with regard to Section 39-1-1. We, however, construe Neely’s motion as being one under SCRA 1986, 5-801(B) (Repl. Pamp.1992), to reconsider and reduce her sentence regardless of her motion’s assertion *709of the basis for jurisdiction. Confinement in a facility where appropriate treatment would be available and where her condition could be monitored more closely by trained medical workers reasonably can be seen as a reduction in the severity of her sentence. Even if it is true, as the State argues, that in a mental facility Neely would lose liberty interests that she would retain in prison, Neely’s view of her request as one to reduce the sentence is not unreasonable. That is how the trial court characterized the relief sought. At the time Neely filed her motion, Rule 5-801(B) provided that a motion to reduce a sentence may be filed within thirty days after the trial court receives a mandate issued by an appellate court.2 See Hayes v. State, 106 N.M. 806, 808, 751 P.2d 186, 188 (1988) (holding Rule 5-801 jurisdictional insofar as filing of motions is concerned). Under Rule 5-801(B), the trial court had subject-matter jurisdiction to consider the motion.
This Court has jurisdiction over this appeal. — The denial of the 5-801 motion is a final, appealable order. The State next argues that appeal from the trial court’s decision is not properly before this Court and that Neely has faded to cite any authority providing for appellate jurisdiction. By the same token, however, the State cites no authority for its contention that there is no right to appeal an order denying modification of a sentence. There are no New Mexico cases on point. Rule 5-801 was originally drafted to mirror the version of Rule 35 of the Federal Rules of Criminal Procedure then in effect. See SCRA 5-801 committee commentary. Therefore, we turn to cases interpreting that version of the federal rule.3 We find that those cases hold that denial of such a motion is a final, appealable order. See, e.g., United States v. Donner, 528 F.2d 276, 279 (7th Cir.1976) (reviewing appeal from denial of Rule 35 motion for reduction of sentence without discussion of jurisdiction), overruled on other grounds by Lawary v. United States, 599 F.2d 218, 222 (7th Cir.1979) (same); Ekberg v. United States, 167 F.2d 380, 383 (1st Cir.1948) (stating that order denying Rule 35 motion is final decision); United States v. Calvert, 443 F.Supp. 508, 510 (M.D.Tenn.1977) (stating that order denying Rule 35 motion is appealable). Having provided a thirty-day period for such a motion to be filed, we believe we should recognize a right to appeal a ruling that constitutes a final order denying the motion. Moreover, an appeal of a life sentence is taken directly to this Court under Article VI, Section 2 of the New Mexico Constitution.
The issue was properly preserved. The State argues that Neely did not preserve the question whether her sentence was illegal or was imposed in an illegal manner and, therefore, those issues should not be reviewed by this Court unless there was jurisdictional or fundamental error. See State v. Gutierrez, 91 N.M. 54, 55, 570 P.2d 592, 593 (1977) (stating that the Supreme Court will not consider objection first raised in defendant’s brief in chief). Neely does not argue that the original sentence was illegal, but rather that the trial court’s denial of her motion on the ground that it had no discretion to craft a sentence other than a mandatory life sentence in a New Mexico penitentiary was improper. The filing of a motion invoking the discretion of the lower court is itself sufficient to preserve any error in the court’s refusal to exercise discretion. Exceptions are not required as long as “a ruling or decision by the district court was fairly invoked.” SCRA 1986, 12-216(A) (Repl.Pamp. 1992).
The trial court’s discretion in sentencing under a guilty but mentally ill verdict does not extend to ordering that the defendant be sentenced to a mental institution. Because Neely was found guilty but mentally ill, her sentence is subject to the provisions of Section 31-9-4:
*710The court may impose any sentence upon a defendant which could be imposed pursuant to law upon a defendant who has been convicted of the same offense without a finding of mental illness; provided that if a defendant is sentenced to the custody of the corrections department, the department shall examine the nature, extent, continuance and treatment of the defendant’s mental illness and shall provide psychiatric, psychological and other counseling and treatment for the defendant as it deems necessary.
Neely relies on language from Neely I to argue that Section 81-9-4 preempts the sentencing statute for first-degree murder. Early in the discussion regarding whether Neely was afforded a fair trial, the Neely I opinion states:
[Section 31-9-4] authorizes different treatment for a defendant found guilty but mentally ill.... Section 31-9-4 ... is permissive. It states that a “court may impose any sentence upon a defendant which could be imposed pursuant to law.” Because the legislature left to the discretion of the trial court the determination of whether the legally-mandated sentence for a straightforward guilty verdict should be applied to the guilty but mentally ill convicted defendant, we believe that the guilty but mentally ill verdict is more than a verdict without a distinction.
Neely I, 112 N.M. at 706-07, 819 P.2d at 253-54 (alteration in original) (footnote omitted). That the trial court has discretion in sentencing was reiterated in our discussion concerning cruel and unusual punishment: “[T]he statute allows the court discretion to sentence a mentally ill defendant to a different sentence than that otherwise authorized, indicating the legislature’s intent not to inflict cruel and inhuman punishment on the mentally ill.” Id. at 709, 819 P.2d at 256. However, the specific question of the extent of discretion allowed a sentencing court was not before us in Neely I.
The extent of the trial court’s discretion is guided by statute. In noncapital-felony cases, the trial court has the statutory authority to reduce the sentence for a conviction of a first-degree, second-degree, or third-degree felony based on mitigating circumstances. See NMSA 1978, § 31-18-15.1 (Repl.Pamp.1990) (granting the authority to reduce the basic sentence for noncapital felonies by up to one-third of the basic sentence). Further, the legislature has made it clear that the trial court has the authority and discretion to suspend or defer sentences unless the defendant has been convicted of a capital felony or a first-degree felony. See NMSA 1978, § 31-20-3 (Repl.Pamp.1990) (stating that any court having jurisdiction may suspend or defer sentence of defendant convicted of “any crime not constituting a capital or first degree felony ”). This authority includes the discretion to order that an individual be confined in a mental institution if the sentencing court finds it necessary. See § 31-20-6(B). Likewise, our Rules of Criminal Procedure allow for reduction or reconsideration of a sentence in cases not involving a death penalty or mandatory sentence. See SCRA 5-801(C) (stating that modification of sentence rule does not apply to the death penalty or a mandatory sentence).
The only relief sought by Neely is to be sentenced to “an appropriate mental facility.” The question before us today is whether the sentencing court has discretion, under Section 31-9-4, to sentence a defendant to a mental facility in cases in which that person has been found guilty but mentally ill of a capital felony. In answering this question, we must read Section 31-9-4 in harmony with Section 31-20-3, which denies a trial court the authority to modify sentences in first-degree felony cases. Section 31-9-4 does not supersede or preempt Section 31-20-3. Thus, we must find that the legislature intended only that Section 31-941 be applied in cases in which the sentencing court has the discretion to reduce, suspend, or defer a sentence. Because Neely was convicted of first-degree murder, the trial court did not have the discretion to sentence her to a mental facility. A person convicted of a capital felony is to be sentenced to imprisonment in a corrections facility designated by the corrections department. See §§ 31-18-14 & 31-20-2(A).
*711It is clear from the language of Section 31-9-4 that the legislature contemplated that some defendants found guilty but mentally ill and sentenced to the custody of the corrections department would require treatment. The statute also states clearly that it is the responsibility of the corrections department to determine whether and to what extent an incarcerated guilty but mentally ill defendant is to receive treatment. See § 31-9-4 (“[T]he department shall examine the nature, extent, continuance and treatment of the defendant’s mental illness and shall provide psychiatric, psychological and other counseling and treatment for the defendant as it deems necessary.”). Therefore, in eases in which a defendant is convicted of a capital or first-degree felony, it is up to the discretion of the corrections department to determine the defendant’s appropriate mental treatment.
Conclusion. Neely’s motion to modify her sentence was within the subject-matter jurisdiction of the lower court pursuant to Rule 5-801. Further, this Court has jurisdiction over the appeal because the denial of the motion was a final, appealable order and Neely properly preserved the question for review. Finally, the legislature has clearly stated that a sentencing court does not have the discretion to modify, suspend, or defer the sentence of a defendant convicted of a first-degree felony. The trial court properly denied Neely’s request that it sentence her to a mental facility; therefore, the order of the trial court is affirmed.
IT IS SO ORDERED.
BACA, FRANCHINI and FROST, JJ„ concurs.
MONTGOMERY, C.J., specially concurs.