John B. Ruklick appeals the sentence imposed following his guilty plea to distributing more than ten grams of LSD in violation of 21 U.S.C. § 841(a)(1), (b)(l)(A)(v) (1988). On appeal, Ruklick cоntends that the district court erroneously believed it could not depart downward under section 5K2.13 of the Sentencing Guidelines, see United States Sentencing Commission, Guidelines Manual, § 5K2.13, p.s. (Nov. 1989) [hereinafter U.S.S.G.], unless diminished mental capacity amounted to a but-for cause of his offense. Ruklick further argues that the district court incorrectly calculated the total weight of the controlled substances for which he was accountable. The record reveals that the district court misunderstood the extent of its authority to consider Ruklick’s diminished mental capacity as a basis for downward departure. Accordingly, we reverse and remand fоr resentencing on this narrow issue.
1. BACKGROUND
On February 23, 1989, the Government indicted Ruklick on three counts of distributing LSD, two counts of distributing MDMA and one count of conspiracy to distribute LSD and MDMA. 1 According to the presentence report, these counts encompassed 211.37 grams of LSD and 77.96 grams of MDMA. The calculation for the weight of the LSD included the weight of the blotter paper containing the LSD. Based on the combined weights for the LSD and MDMA, 2 the Guidelines dictated a sentеncing range of 151 to 188 months imprisonment notwithstanding that Ruklick was a first-time offender and had demonstrated affirmative acceptance of responsibility.
On April 25, 1989, Ruklick pled guilty to one count of distributing LSD. The plea agreement dismissed the remaining counts against Ruklick, but left the drug quantity open. At sentencing, Ruklick argued that the weight calculation for the LSD should not include the weight of the blotter paper. The district court rejected this argument and adopted the presentence report’s calculation of drug quantity. At that time, Ruk-lick presented no other objections to the drug quantity calculations.
In addition, Ruklick argued for a downward departure premised on diminished mental capacity under U.S.S.G. § 5K2.13. In support of this theory, Ruklick presented еvidence that his offense resulted, in part, from emotional difficulties stemming from a childhood illness. Specifically, in third grade, Ruklick developed а degenerative joint disease that required Ruklick to wear a leg brace and resulted in six surgeries. As a result of this illness, Ruklick withdrew from his peer group аnd ultimately sought refuge in musical subcultures. By seventh grade, Ruklick had developed an obsession with the Grateful Dead, a rock band that reportedly sаnctioned illegal drug use. According to one *97 psychological expert, Ruklick, age twenty-one, functioned at the level of a twelve-year-old. Additionally, this expert opined that Ruklick suffered from a long-standing schizoaffective disorder that anteceded drug abuse and impaired Rukliek’s judgment.
Based on the above evidence, the district court made the following factual findings:
The Court concludes that the Defendant has been shоwn by reliable and convincing evidence to have a significantly reduced mental capacity. The Court finds that the mental capacity wаs in part reduced by the underlying mental illness or psychiatric problem ... and ha[s] in part led to the unlawful drug use and drug dealing that came on.
Sent. tr. at 82-83. Nevеrtheless, the district court refused to depart downward, citing the following rationale:
I am concerned ... that there is not really a clear showing here that the offense would not have been committed but for the mental illness; because there was a great deal in the background of this yоung man that was not caused by the mental illness; a great deal that had to do with environmental, family and other problems that I do not believe was intеnded to cause a departure. The Court finds it’s very difficult to sort out precisely why John Ruklick committed the drug offenses.
The bottom line here is that the Court believes that the Defendant has shown no basis for a departure from the guideline range in this case. And the Court concludes that the reduced mental capacity is not shown to have been so significant as to have brought about the criminal behavior and made necessary his commitment of this offense and made appropriate a departure from the appropriate guidelines.
Sent. tr. at 83-84.
This appeal followed.
II. DISCUSSION
A. Downward Departure
Ruklick contends that the district cоurt erroneously concluded that it could not depart downward from the Guidelines under section 5K2.13 unless diminished capacity amounted to a but-for сause of Ruk-liek’s offense. We agree.
Ordinarily, the district court has great discretion to determine the appropriateness of a downwаrd departure. United States v. Yellow Earrings,
In the instant cаse, the district court denied a departure on the grounds that Rukliek’s reduced mental capacity was not the sole cause of his drug-relatеd offense. The Guidelines policy statement for diminished capacity, however, contains no such requirement. Rather, that Guidelines section рrovides:
Diminished Capacity (Policy Statement)
If the defendant committed a non-violent offense while suffering from significantly reduced mental capacity not resulting from voluntary use of drugs оr other intoxicants, a lower sentence may be warranted to reflect the extent to which reduced mental capacity contributed to the commission of the offense, provided that the defendant’s criminal history does not indicate a need for incarceration to рrotect the public.
U.S.S.G. § 5K2.13. Thus, the express language of the policy statement does not require proof amounting to but-for causation. Acсordingly, we interpret section 5K2.13 to authorize a downward departure where, as here, a defendant’s diminished
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capacity comprised а contributing factor in the commission of the offense.
See United States v. Spedalieri,
B. Calculation of Drug Quantity
On appeal, Ruklick raises a number of issues pertinent to the calculation of drug quantity. The only issue presented to the district court, however, is Ruklick's contention that the weight of blotter paper should not be included in weight ~alcula-tions for LSD offenses. An Eighth Circuit panel has already addressed the blotter paper issue and resolved it adversely to Ruklick's position. United States v. Bishop,
III. CONCLUSION
The district court erroneously underestimated its authority to consider a downward departure based on the contributory effect of Ruklick’s diminished mental capacity. Accordingly, we reverse Ruklick’s sentence and rеmand for a reconsideration of the departure issue. In all other respects, we affirm.