"I tell you what, you're gonna either show me your driver's license or you're gonna wind up getting a ticket. I'll tow your car and lock you up," the officer threatened, but in the end Smith was merely ticketed, possibly for excessive noise from a vehicle. Smith says he plans to challenge the ticket, so we'll find out whether it's illegal to honk at a cop.
"Just Laid on the Horn for a Minute"
"The light turned green and the car in front of me just sat there," Smith told the Riverfront Times. "So I honked once and he started to scoot forward, then just like hit his brakes real hard. So I honked again and he started to go forward and kinda threw his arms up, but wasn't really moving, still just blocking the way. So then I just laid on the horn for a minute as he slowly crept forward." The officer changed lanes, and, after Smith passed him, turned on his lights and pulled Smith over, and their heated exchange is worth hearing:
After 45 minutes and a discussion with three other officers who arrived on the scene, the first officer told Smith he'd be getting a ticket in the mail because the printer in another officer's car was broken. Although Smith was never told what that ticket would be for, he told the Times the officer had mentioned something about "excessive noise" coming from his vehicle.
Missouri's traffic statutes do say that "no vehicle shall be driven in such manner or condition that excessive and unnecessary noises shall be made by its machinery, motor, signaling device, or other parts," and a different section warns that horns "shall be used for warning purposes only and shall not be used for making any unnecessary noise."
We know that you can insult a cop, and even flip off a cop, but whether Missouri law prohibits honking at cops stopped at green lights remains to be seen.