Questions arise from time to time on the use of Blackjack Card Counting Computers, like Casey, or George, in a casino. These devices date back to David, built by Keith Taft in 1971. The following is from Nevada Senate Bill 467 signed into law in 1985:
"It is unlawful for any person at a licensed gaming establishment to use, or possess with the intent to use, any device to assist in projecting the outcome of the game."
The penalty for the first offense is 1 to 10 years, up to $10,000, or both. The second offense includes mandatory imprisonment. Keith Taft’s son was convicted for cheating for using such devices even before this law was passed. Casinos will no longer cut your fingers off. But, if you are caught with a Blackjack computer in a casino - you will find that they have no sense of humor.
Ken Uston is often quoted in discussions of Blackjack computers. It is important to understand that his experience was before this law was signed. Uston later said that you may as well bring a gun and rob the casino since the penalty is about the same.
Mississippi, New Jersey, Colorado, etc. have similar laws.
It should also be pointed out that the design and technology in these computers is very old. Many important developments have occurred since. Not only is it legal, but you will actually see better results by leaving the Blackjack computer at home and using your brain. Note also that use of the machines is not trivial. It takes substantial practice to master entry of the cards. Much simpler to count in my mind. Practice and analysis on a computer is still legal. Just keep it out of the casinos.
Update: In 2009 an iPhone application was offered for sale as a card-counting device. This application is reported to use card counting instead of perfect combinatorial analysis used by some of the prior computers and also miscalculates the true count by ignoring neutral cards. It appears to be inferior to human counting while violating the law.