I am aware of the testing methods for rapid results; however my reference to RAT test was an example as how modern detection methods use a similar colour change methodology. In this case the Pathologist would draw urine from the cadavers bladder for quick analysis, obviously to prove or dispel drugs in his system.
“The autopsy found no evidence that he had drugs within the 72 hours before the incident,”
This makes no sense at all. It suggests 3 days prior he had his bloods analysed. At his autopsy a blood sample would be taken and sent for toxicology for analysis; this test takes 4-6 weeks. I'm suggesting they did a rapid antigen test by saliva or air squeezed from bronchus and obtained a NEG reading, mimicking the reading obtained from a road-side breath testing device.
RIP...however; where is it written he was drug addicted, or even under the influence? He is not a serving officer; he was dismissed more than a year ago. His bloods will be analysed and the results available in 4-6 weeks.