So, near my current house there is a small storefront with a "Secretary of State Police" sign out front. I had no idea what that unit does, so when I saw a uniformed officer buying lunch ahead of me at the local Subway I asked.
Turns out that the
Secretary of State Police is the oldest statewide police unit in Illinois, celebrating their 100th year. They have two main duties. First, they enforce the laws on motor vehicles, especially sales thereof. So, they make sure junkyards, car dealerships or auto body shops aren't buying stolen cars. Second, they provide the uniformed security for the state capital building and associated office complexes.
Now I know.