Everybody in baseball steals signs, and it's legal. It's not legal to do what the Astros did, using electronics to do it.
Sign stealing in football is legal. My senior year, I was the manager for the alumni team in the old Varsity-Alumni game and knew our varsity signal system. This was Barry Switzer's "first game" as OU's head coach. I whispered to one of the alum players what was coming three or four plays in a row. He told the coach, who asked if I could tell him what was coming, and I reluctantly told him I could. And so for two series late in the game, the alums shouted the plays and stopped two straight series.
It really pissed off Galen Hall who taught me the signals earlier in the football season. So I stopped. But when I coached kids' football for 30 years, I used those same signals, and threw in a rubik's cube for the colors for certain things. A guy in that league one year, told me after the season he spent the whole season trying to learn my signals. All the games were at the same city field, and virtually all the coaches watched every game. This was
But he told me he could never figure out what the rubik's cube was for. It was the simplest thing, but it kept them from learning the whole system. I never was in a league against him again, or I would have changed them