From what I've read, it was a wardrobe malfunction -- gun was in a IWB holster covered by a jacket, the jacket rode up briefly when he sat down, and a sheep saw it and called 911.
The ignoring-the-police-when-they-started-barking-at-him part might have been him seeing the potential for $$$$$$, or maybe he thought it was the best way to avoid being shot (like Erik Scott.) Or maybe he just had no idea what was going on.