Headlights On or Off When Wipers Are On?

Saturday, it was a little rainy in town so I I turned my wipers on and my headlights. My friend asked if it was state law in Kentucky for headlights to be on when wipers are in use? I had no idea. She lives in Tennessee and said it is the law there. Off to researching I went. 

I found out in June of 2013, a bill was pre-filed to require wipers on, headlights on in Kentucky on vehicles that were 2000 or newer. I went to consult with old handy dandy Kentucky Driver's Manual and I found no connection to both pieces of equipment had to be on at the same time. Here's something interesting, in the "Windshield Wiper" section of required equipment in Kentucky, it says a wiper must be on the driver's side, um, huh? It makes sense, but does a passenger want to be left in the dark?

Illinois is the only state in the Tri-State that has a "wipers on, headlights on" law/requirement. I guess if a vehicle has running lights, which aren't always the main headlights, what's the law then?