I was driving behind a pickup on the way home a few weeks ago, and thought the driver was DUI. The road is full of curves(I think they followed a snake trail when they built the road) and this guy was over the lane dividing stripes one minute and then almost in the ditch.
I followed him for over five miles and was afraid to pass, as were the other drivers. I wasn’t in that big a hurry to have a crash with him, so I just followed at a safe distance. As we came into a small town, he hung up his cell phone. After that, he drove normally.