A man walks into a bar and sees a sign that says, "Free drinks for the person who can make our horse laugh." Intrigued, the man asks the bartender about the challenge.
The bartender explains that they have a horse in the back who never seems to be in a good mood and they want to see if anyone can make him laugh. The man thinks for a moment and decides to give it a try.
He walks into the back and whispers something in the horse's ear. To everyone's surprise, the horse bursts out laughing hysterically. The man walks back to the bar and claims his free drinks.
The bartender is amazed and asks the man, "What did you say to the horse to make him laugh like that?"
The man replies, "I told him I work for the IRS and I need to see his tax returns!"