I can't remember the specifics, because it was so long ago, but they did win. The woman had pulled out to pass a transport truck and the transport accelerated,
in order to block her from passing. There was oncoming traffic so she had to speed up significantly to get around the truck, which was when OPP clocked her.
*EDIT* Found it. On appeal it ended up changing how the stunt driving charge is applied. It was originally an "absolute liability offence" which means if you did it, you're guilty. Circumstances are irrelevant. It's now applied as a "strict liability offence" which means that if you did it, you're guilty, but you can use the defence that you used "all reasonable care" in the situation and had no recourse, as a defence.
Jane Raham admits she panicked when she pushed on the accelerator to overtake the tractor-trailer.
www.thestar.com