People v. PritchardPeople v. Pritchard
BERNSTEIN, J.
Defendant appeals his conviction by a jury of a violation of
At the trial the People‘s expert testified that the results of an intoxilyzer test administered to appellant were 0.11 percent and 0.12 percent. He further testified that the machine had an error factor of .005. However, in order to convert the breath reading to that of a blood-alcohol reading for purposes of
(1) In order to support a conviction of a violation of
(2) There was evidence presented that the breath test results for appellant were 0.11 percent and 0.12 percent; that the margin of machine error was .005, which when applied to the aforementioned 0.11 percent and 0.12 percent machine readings as required by People v. Campos, supra, still produces a test result of 0.10 percent or more.1
However, in addition to the possibility of machine error, there is also the possibility of variation in the partition ratio as applied to the individual defendant. A breath test was given appellant. In order to convert the breath reading to that of a blood-alcohol reading for purposes of Vehicle Code
The People can readily ascertain the individual machine‘s margin of error, for the machine is in their possession. However, the individual partition ratio is an individual physical characteristic of the defendant, and presumably can only be obtained through means of physical tests upon him. The defendant is in control of this information or at least of access to it.2 With the foregoing in mind, the question becomes who should bear the burden of proof in establishing the partition ratio of the individual defendant, the People or the defendant?
We note that in response to the dangers posed to the public by the drunk driver, the Legislature has enacted certain presumptions in order to facilitate prosecution of these offenders. (Burg v. Municipal Court, supra, at p. 264.) Indeed, it is statutorily presumed that a person driving with a blood-alcohol level of 0.10 percent or more is a danger to the public (
In order to deal with the situation where an exonerating fact is peculiarly within the defendant‘s knowledge, and proof of its nonexistence by the prosecution would be relatively difficult or inconvenient, the courts have established “the rule of convenience” whereby the initial burden of producing evidence on the issue is placed on the defendant. (People v. Montalvo (1971) 4 Cal.3d 328, 334 [93 Cal. Rptr. 581, 482 P.2d 205, 49 A.L.R.3d 518]; People v. Yoshimura (1979) 91 Cal. App.3d 609, 626-629 [154 Cal. Rptr. 314]; People v. Boo Doo Hong (1898) 122 Cal. 606 [55 P. 402].)
Further, application of the rule of convenience to the partition ratio comports with this legislative scheme to facilitate the prosecution of drunk drivers. Application of the rule in this situation is not unduly burdensome to the defendant as he has the option of electing to eliminate this potential problem by taking the blood test, when it is offered pursuant to
We hold that the rule of convenience applies as to the partition ratio, and by its operation the defendant is in effect presumed to have a 2,100 to 1 partition ratio unless he presents evidence as to his personal partition ratio which establishes that the 2,100 to 1 ratio is not valid for him. General evidence of such a possibility of error in the partition ratio will not suffice to rebut this presumption. As no such evidence was presented in the case at bench, the presumption was not rebutted; the general evidence of a possible 10 percent margin of error in the partition ratio was without consequence for the defense. We hold there was sufficient evidence presented to support the conviction. (See People v. Johnson (1980) 26 Cal.3d 557, 562 [162 Cal. Rptr. 431, 606 P.2d 738, 16 A.L.R.4th 1255].)
The judgment is affirmed.
Reese, P.J., and Shabo, J., concurred.