Card counting is perfectly legal — all a counter does is attempt to keep track of whether the cards remaining in a deck are favorable to his winning a hand (mainly if there are lots of tens and aces remaining in the deck) — but it's deeply frowned upon by Vegas casinos. Those caught counting cards are regularly expelled from casinos on the spot and are often permanently banned from returning.
But given the slim house odds on Blackjack, it's often said that a good card counter can actually tip the odds in his favor by carefully controlling the way he bets his hands. And Vegas really doesn't care for that.
The anti-card-counter system uses cameras to watch players and keep track of the actual "count" of the cards, the same way a player would. It also measures how much each player is betting on each hand, and it syncs up the two data points to look for patterns in the action. If a player is betting big when the count is indeed favorable, and keeping his chips to himself when it's not, he's fingered by the computer... and, in the real world, he'd probably receive a visit from a burly dude in a bad suit, too.
The system reportedly works even if the gambler intentionally attempts to mislead it with high bets at unfavorable times.
The system is still in the academic/development stage, but casinos are always eager to experiment with high-tech systems that foil gamblers in their attempts to leave the joint with money in their pockets. Don't be surprised to hear that this one is actually rolled out in the months ahead..."
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