On the night of May 16, 1995, Joseph E. Weeks and Bill Anderson were dining together at Applebee’s restaurant in Columbus where the two often met. Anderson at one point went to the restroom. Viewed most favorably to the verdict, the evidence showed that Weeks followed Anderson into the restroom and shot him in the back of the head at close range. Anderson died from the wound two days later. Weeks was charged with murder and found guilty but mentally ill (“GBMI”). The trial court sentenced him to the maximum term of sixty years imprisonment. In this direct appeal, Weeks challenges the jury’s rejection of his insanity defense and the reasonableness of the sentence. We affirm the conviction and revise the sentence to the presumptive term of fifty years.
I. Insanity Defense
Weeks’s defense at trial was insanity. He therefore had the burden of establishing by a preponderance of the evidence that “as a result of mental disease or defect, he was unable to appreciate the wrongfulness of the conduct at the time of the offense.” Ind. Code §§ 35-41-3-6(a) & 35-41-4-l(b) (1993). When an insanity defense is interposed, the trier of fact has the additional options of returning a verdict of either “not responsible by reason of insanity at the time of the crime” or “guilty but mentally ill at the time of the crime.” Ind.Code § 35-36-2-3 (1993). “Mentally ill” is defined as “having a psychiatric disorder which substantially disturbs a person’s thinking, feeling, or behavior and impairs the person’s ability to function.” Ind.Code § 35-36-1-1 (1993).
Weeks argues that the jury’s verdict of GBMI was erroneous because he proved by a preponderance of the evidence that he was unable to distinguish right from wrong at the time of the crime. Although insanity and GBMI both require proof of some form of mental disorder or impairment, a finding of insanity also requires a showing of the defendant’s inability to understand the wrongfulness of the criminal conduct; mental illness alone is not a defense to a crime.
Gambill v. State,
II. Sentence Review
Weeks next contends that the trial court erred in imposing the maximum term of sixty years. Although the decision to enhance or reduce a sentence is generally within the trial court’s discretion,
Archer v. State,
In arguing that his sentence should be reduced, Weeks makes two points: (1) the second factor is not a valid aggravating circumstance; and (2) the trial court erred in failing to find his mental illness to be mitigating. Weeks is correct that the “depreciate seriousness” aggravator may not be used to enhance a sentence; rather, it is relevant only to determine whether a reduced sentence should be imposed.
See, e.g., Widener v. State,
Now, it may very well be ... that a part of [a] finding of guilty, but mentally ill [is] that the maximum sentence ... is the same as the presumptive sentence. Well, maybe I don’t get it or maybe I think the circumstances in this case are different, but it appears to the court that there are sufficient aggravating circumstances and that the crime itself warrants the imposition of an enhanced penalty beyond the presumptive.
The court also stated: “It is difficult to separate out what is happening, or what did happen in this case from Mr. Weeks’s mental situation.” However, the trial court ultimately found that there were no mitigating circumstances. In this respect the court erred.
We have emphasized that a GBMI defendant “is not automatically entitled to any particular credit or deduction from his otherwise aggravated sentence” simply by virtue of being mentally ill.
Archer,
Applying these criteria here, we agree with Weeks that the trial court erred *31 in not finding Ms Mstory of mental illness— and the jury’s verdict of GBMI — to be of some mitigating value. Uncontradicted evidence showed that Weeks was first diagnosed with schizophrema in 1989 when he was twenty-seven years old. 1 Between 1989 and 1995, Weeks was in and out of hospitals and was diagnosed as having a range of disorders, including schizophrenia, schizo-affective disorder, and bipolar disorder. These evaluations are consistent with others offered at trial as to Weeks’s mental condition after the offense. Indeed, the State does not dispute that Weeks has an extensive and apparently unbroken history of mental illness dating to 1989. His mental problems were not completely debilitating: if Weeks took a range of medications, he could function fairly normally much of the time, although with some delusional and grandiose thought patterns. For example, several witnesses testified that Weeks would frequently steer conversations towards government conspiracies, aliens, and other science fiction themes. Several witnesses who knew Weeks — including his parents, his employer at the time of the shooting, and several doctors who had evaluated him — testified that they did not regard him to be dangerous. One of the arresting officers testified that Weeks was calm after being taken into custody on the night of the shooting. A videotaped interrogation of Weeks that occurred several hours after his arrest shows no hint of aggression.
Pointing to this evidence, the State argues that there was little or no link between the crime and Weeks’s mental infirmities. Weeks replies that there is “ample evidence” that Ms mental illness caused him to kill Anderson. The expert testimony on which Weeks relies for this proposition, if credited, shows only that Weeks was, or may have been, delusional on the night of the shooting, not that there was necessarily a connection between any delusions and the crime. At no pomt did Weeks assert that voices, visions, or hallucinations caused him to act as he did. Weeks testified at the sentenemg hearing that although he was dming with Anderson at Applebee’s on the mght that Anderson was shot, Weeks did not believe that he killed Anderson and that if he did, he did not know why. In the videotaped statement Weeks gave to police shortly after the shooting, he claimed not to know why he was m custody or what had happened to Anderson. This behavior is consistent with Weeks’s occasional inability to control his impulses. For example, eight months before the crime, Weeks ran out of gas on Interstate 65 near Indianapolis. Police found him standmg naked near Ms ear on the side of the freeway, mumbling about “black gashes of cancer” in the veMcle. In 1993 he was involuntarily hospitalized after he threatened to “blow away” his parents with a shotgun. One doctor who examined Weeks about a month before the killing concluded that Weeks might have an escalation of symptoms due to decreased medication. Weeks and Anderson were friends and there is no claim that Weeks had any motive for the killing or planned it in advance. Weeks’s apparently spontaneous act of following Anderson to the restroom and shooting him, as well as Weeks’s denial of the incident after the fact, are consistent with, if the not the obvious product of, his mental impairments.
In sum, although there is no clear nexus between Weeks’s illness and the killing, there is sufficient showing of his erratic behavior to require that his illness be considered in sentencing. As
Archer
noted, murders often present “egregious” facts,
id.
at 686, that shock the conscience. This ease — an execution-style shooting — is another in that unfortunate line. In light of Weeks’s serious cognitive disorders of chronic duration, however, we conclude that mental illness as a mitigator offsets the enhancing value of the factors cited by the trial court. Accordingly, we will reduce the sentence to the presumptive term of fifty years. Although the Indiana Constitution does not require comparative proportionality review,
Gambill,
Conclusion
The conviction is affirmed and the sentence is revised to fifty years imprisonment.
Notes
. Weeks testified at the sentencing hearing that he believed his mental problems could be traced to an incident in 1987 in California in which he was kidnapped by an alien spaceship.
