I had about the same thing happen a few months ago. A car almost hit me in traffic and as I was following him it was obvious the guy was drunk. Kept swerving from lane to lane, running off the edge of the road, etc.
I got on my cell phone and dialed 911 and the dispatcher was a total ass. I was trying to give him the license number and location, all the while trying to drive, and he kept telling me to answer his questions and not to give him the info I was trying to give him. I tried to explain we were in heavy traffic and I was trying to drive, so I needed to get the info out to him as quickly as I could, but he kept stopping me and generally being rude.
The other car finally got away from me in traffic, but I called the Sheriff's office and registered a complaint against the 911 guy. Here I was, trying to be a good citizen and keep an accident from happening, and the dispatcher wouldn't take the info I was providing.
Don