Sure you can. You can make a legal requirement that somebody has to be licensed to sign off on things that require the license without fining for the use of the word. Imagine that you're an engineer in Germany, you go to Oregon and somebody asks you what you do for a living. You reply with "I'm an engineer" and get fined because you're not licensed in Oregon.
In an oddly mirrored version, up until about 12 years ago it was illegal for someone with a PhD from outside the EU to use the title "Dr." in Germany, without going through specific paperwork to get permission to use that title.
> At least seven U.S. citizens working as researchers in Germany have faced criminal probes in recent months for using the title “Dr.” on their business cards, Web sites and resumes. They all hold doctoral degrees from elite universities back home
