State of California vs. Connelly

Here's a piece of teatime fun that fulfils resolutions 10 and 11, playing with physics and furthering the public understanding of science. Well, if you count a California magistrate's court as the public that is.

My mate Jim got pulled over for speeding in the summer - he reckons he was doing about 85 (he was late for football), the policeman said that he had to do 106 to catch Jim. Going over 100 changes the offence to something more like dangerous driving, which carries a heavier fine. At the arraignment Jim pleaded not guilty to the higher charge, and is in court today (where he can cross-examine the officer). After talking about it last night I worked out two arguments for him, one using some understanding of experimental errors to suggest that the officer's speed estimate is not good enough to put the charge beyond reasonable doubt (I felt like a film star writing that one, I can tell you), and the other being basically that a low-relative-speed chase with the cop going at 106 and Jim going at 100 would have lasted for a ridiculous-sounding, 3-intersection-spanning 2.4 miles. We'll see what the judge says later this afternoon...