> By far, the most common way people cheat is to store a fish basket or pet taxi under a dock, filled with lunkers they’d caught before the event, and then retrieve the fish while they were supposed to be out fishing. A variation on this would be to attach a string to a stump in the water and hook various fish to the string. This way allows fishermen to retrieve the fish while faking that they actually caught them, just in case they were paired up in the boat with a competitor. There was the story that Ray Scott told me about a man who showed up for a tournament wearing a full-length raincoat even though there wasn’t a cloud in the sky — his partner later discovered the man had a string of bass draped around his neck. There was the guy in the U.K. who last year won a bass fishing tournament with a 13-pounder, only to have the second-place finisher recognize the giant bass from a recent trip he had taken to the local aquarium with his daughter. They called the aquarium and, sure enough, it was missing a big bass. People have been caught buying fish off of noncompetitors on the lake during an event, or sharing fish between colluding teams.

Article doesn't mention it, but seems like you could easily brute force it - if the prize money is big enough you simply have your friend scuba dive in the lake with a closed system and in possession of a huge pre-caught bass. Then you meet at a predetermined spot in the lake where your friend attaches the fish to your hook and you reel it in. Then you split the prize later. This would only work on big lakes though or there would be witnesses of a scuba diver exiting the lake at some point.