Trial court did not err in overturning administrative suspension of driver’s license where Kern County Regional Crime Lab used incorrect procedures in performing and reporting blood tests. The Department of Motor Vehicles (DMV) suspended Najera’s driver’s license after it found that he drove with a blood alcohol concentration (BAC) of .08% or more (Veh. Code, § 13353.2). At an administrative hearing, Najera presented expert testimony challenging the manner in which the blood test results were conducted and reported by the Kern County Regional Crime Laboratory. The expert faulted the undersized sample taken, which was smaller than recommended and could lead to unreliable results. Further, the crime lab failed to report both columns of data from the gas chromatograph. The expert testified that one column of data can only tentatively show the sample contains alcohol; data from the second column is required to reach a scientifically valid conclusion. The expert also faulted the crime lab’s lack of quality control. The hearing officer upheld the suspension and Najera sought writ relief. The superior court found that Najera’s expert had successfully rebutted the presumption the test results were valid, based on the lab’s failure to report both columns of data. It granted a writ of mandate. The DMV appealed. Held: Affirmed. The DMV had the burden of proving by a preponderance of the evidence that Najera’s BAC was .08% or more, which can be done by submitting blood test results. (See Cal. Code Regs., tit. 17, § 1215, et seq.; Evid. Code, §§ 664, 1280.) The burden then shifted to the Najera to show the test was improperly performed. Najera’s expert’s testimony regarding the crime lab’s failure to report data from both columns of the gas chromatograph rebutted the presumption that the test results were reliable. The burden then shifted back to DMV, but DMV failed to present any additional evidence to show the results were in fact reliable.