People v. Pritchard

• Decision Date: 25 October 1984
• Docket Number: No. 21591,21591
• Court: California Superior Court
• Parties: 162 Cal.App.3d Supp. 13 The PEOPLE, Plaintiff and Respondent, v. Kelton Ray PRITCHARD, Defendant and Appellant. Crim. A. Appellate Department, Superior Court, Los Angeles County, California

Page 314

209 Cal.Rptr. 314

162 Cal.App.3d Supp. 13

The PEOPLE, Plaintiff and Respondent, v. Kelton Ray PRITCHARD, Defendant and Appellant.

Crim. A. No. 21591.

Appellate Department, Superior Court, Los Angeles County, California.

Oct. 25, 1984.

[162 Cal.App.3d Supp. 14] John A. Slawson, Redondo Beach, for defendant and appellant.

Robert H. Philibosian, Dist. Atty., Donald J. Kaplan and Eugene D. Tavris, Deputy Dist. Attys., for plaintiff and respondent.

OPINION AND JUDGMENT

BERNSTEIN, Judge.

Defendant appeals his conviction by a jury of a violation of Vehicle Code section 23152, subdivision (b) (driving with a blood-alcohol level of 0.10 percent or more). He was acquitted of driving while under the influence (Veh.Code, § 23152, subd. (a)). On appeal he contends that the evidence presented was insufficient to support the conviction.

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 Vehicle Code section 23152, subdivision (b) a partition ratio must be used. The expert testified that there could be an error factor of 10 percent in the partition ratio used. Appellant contends that if this 10 percent error margin in the partition ratio is applied to the 0.11 percent machine reading, the result would be less than 0.10 percent; therefore, pursuant to People v. Campos (1982) 138 Cal.App.3d Supp. 1, 188 Cal.Rptr. 366, there was insufficient evidence presented to establish that he was driving with a blood-alcohol level of 0.10 percent or more.

In order to support a conviction of a violation of Vehicle Code section 23152, subdivision (b), "the People ... must prove beyond a reasonable doubt that at the time he was driving [the defendant's] blood alcohol exceeded 0.10 percent." (Burg v. Municipal Court (1983) 35 Cal.3d 257, 265, 198 Cal.Rptr. 145, 673 P.2d 732.) Generally this will have to be established by circumstantial evidence. (Id., at 266, fn. 10, 198 Cal.Rptr. 145, 673 P.2d 732.) Therefore in order to sustain such a conviction, the People must present sufficient evidence from which it could reasonably be deduced that the defendant's blood-alcohol level was 0.10 percent or more (see People v. Reilly (1970) 3 Cal.3d 421, 424-425, 90 Cal.Rptr. 417, 475 P.2d 649; see, also, People v. Campos, supra ). The question presented is whether such sufficient evidence was presented in the instant case. We hold that it was.

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 section 23152, subdivision (b), a partition ratio must be used. A blood-breath ratio of 2100 to 1 was used as mandated by title 17 of the California Administrative Code (Cal.Admin.Code, tit. 17, § 1220.4, subd. (f)). This is called the partition coefficient or partition ratio. However, there can be an error factor of 10 percent in the partition ratio of 2100 to 1. (At the trial the expert testified that 95 percent of the population falls within this 2100 to 1 plus or minus 10 percent range.) The issue we are confronted with is whether, absent any evidence as to the defendant's actual partition ratio, this 10 percent error margin is also to be considered in determining whether the machine results establish that the defendant's blood-alcohol level was 0.10 percent or more.

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, 35 Cal.3d at p. 264, 198 Cal.Rptr. 145, 673 P.2d 732.) 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...