delivered the opinion of the court:
Defendant, Donald Cochran, was indicted for murder in February of 1973 and subsequently found unfit to stand trial until September of 1985. On December 9, 1985, after a bench trial, defendant was found to be not guilty by reason of insanity. In January of 1986, the circuit court of Jefferson County found defendant to be subject to involuntary commitment for the term of his natural life. Defendant appeals from this order arguing that the court erred in ruling that a term of natural life is the upper limit for release under the not guilty by reason of insanity statutes.
Section 5 — 2—4(b) of the Unified Code of Corrections (Ill. Rev. Stat. 1985, ch. 38, par. 1005 — 2—4(b)) provides in part:
“If the Court finds the defendant subject to involuntary admission *** [s]uch period of commitment shall not exceed the maximum length of time that the defendant would have been required to serve, less credit for good behavior, before becoming eligible for release had he been convicted of and received the maximum sentence for the most serious crime for which he has been acquitted by reason of insanity.”
It is the court’s duty under this statute to determine by reference to the relevant sentencing scheme the maximum sentence that could have been imposed upon conviction for the most serious crime charged, less credit for good behavior. (People v. Tanzy (1983),
Section 5 — 8—l(aXl) of the Unified Code of Corrections (Ill. Rev. Stat. 1985, ch. 38, par. 1005 — 8—1(a)(1)) provides that the term for murder shall be not less than 20 years and not more than 40 years. Section 5 — 8—1(a)(1) also provides that if the court finds the murder was accompanied by exceptionally brutal or heinous behavior indicative of wanton cruelty, natural life imprisonment can be imposed. Defendant argues the legislature never intended to include natural life as a “maximum sentence” or a maximum criminal commitment period for an insanity acquittee. Defendant further contends the extended-term provisions set forth in section 5 — 8—2 of the Unified Code of Corrections (Ill. Rev. Stat. 1985, ch. 38, par. 1005 — 8—2) are not applicable to section 5 — 2—4(b) commitment. We disagree in both instances.
In construing a statute, we must look first to the words employed by the legislature. We may not alter the plain meaning of those words or read any limitations into the statute that do not exist. (See, e.g., People v. Larson (1985),
Defendant argues, however, based on People v. Larson (1985),
Having determined that the maximum period of criminal commitment under section 5 — 2—4(b) can include natural life (as well as the extended terms of section 5 — 8—2), we still must remand this cause for further proceedings. It is unclear from the record before us whether the trial court believed natural life is always required when dealing with an insanity aequittee who committed murder or whether the court found this murder to be accompanied by exceptionally brutal or heinous behavior indicative of wanton cruelty. While we hold that natural life is a permissible maximum commitment period, it must be supported by a finding of the existence of factors in aggravation. (See Larson,
Reversed and remanded, with directions.
HARRISON, P.J., and WELCH, J., concur.
