How to Catch a Cheater in a Tournament

It's really pathetic this but it is really interesting how they caught him and running this against the computer here's a chart of his scores in these tournaments. And he said he didn't cheat in any of the games. Where they were live streaming but they've proven that wrong sexHow does he cheat in person then less the thing no one really knows, I don't want to overly judge until they have hard pre- proof that he was cheating.