In People v. Carpenter (1997) 15 Cal. 4th 312, the "Trailside Killer" was found guilty of murdering seven hikers, some of whom he also raped. ( Id. at p. 344.) On appeal, he challenged the use of prior crimes evidence, which was used to prove intent and state of mind. ( Id. at pp. 380, 382-383.) Rejecting the argument that prior crimes must be established by clear and convincing evidence, the California Supreme Court held that prior crimes only need to be established by a preponderance of the evidence. ( Id. at p. 382.) The court went on to explain the permissive inferences as follows: "The more often defendant killed or raped, the more likely he (1) intended (and premeditated) the result actually achieved, (2) intended to fulfill his statement of intent to rape Hansen, and (3) intended to kill Haertle although Haertle survived. Stated differently, evidence that defendant killed and raped before he shot Hansen and Haertle reduced the likelihood that . . . he did not intend to kill or rape. This simple logic required no complex instructions." ( Id. at p. 383.) In Carpenter, the defendant argued that the jury instruction permitting the jury to consider prior crimes proved by a preponderance of the evidence reduced the prosecution's burden of proof on the mens rea element of the offenses. ( Id. at pp. 380, 383.) Noting that the standard instructions on reasonable doubt and on the sufficiency of circumstantial evidence for proving specific intent were also given at trial, the court concluded that the instructions as a whole were clear that the prosecution still had to prove intent beyond a reasonable doubt. ( Id. at p. 383.)