Why is there a tiny typo on the Tennessee driver's license?

Have you ever looked closely at your Tennessee driver’s license? There might be something surprising in the fine print. Curious Nashville listener Sam Barocas used his microscope to find it. And then he asked:Why is there a microscopic typo on the Tennessee driver’s license?In some instances — likely on millions of licenses — a thin ribbon of text reads “The VolunDeer State.” With a ‘d.’Among the theories: It’s a genuine mistake. It’s an intentional security feature. It’s an easter egg tucked in by a mischievous designer. WPLN’s Justin Barney helps Curious Nashville get to the bottom of this mystery.