In terms of restrictions, we have found that Alabama is a moderately restrictive state on gambling, in general terms, because the letter of the law states that individuals may run afoul of the law when acting merely as players, whereas most states just focus on operators.

The state makes it a Class C Misdemeanor to, “Knowingly advance or profit from unlawful gambling activity as a player,” though as a practical matter, we cannot find any instance of anyone facing prosecution for the mere act of playing online. For one thing, the authorities would have very little interest in prosecuting that, and secondly, how would they know?
The state also makes it illegal to “Possess a gambling device,” as a Class A Misdemeanor. To quote from the statute, "Any other gambling device, with the intention that it be used in the advancement of an unlawful gambling activity." In other words, your computer could technically constitute possession of a gambling device if you are using it for the purposes of gambling.
With Respect to Online Gambling
The only really clear thing that a person or business may not do is operate an online casino out of the state. Of course, that’s true of every state in the United States (mostly due to the UIGEA, which is a Federal statute) unless the state in question has commercial casinos and has authorized those commercial casinos (such as in New Jersey) to conduct online gambling operations. Even then, those operations would be restricted to only accepting customers located in the state that authorizes and regulates online gambling.
The laws in Alabama are otherwise...
...fairly ambiguous when it comes to mere players, and the only enforcement measures ever taken have had to do with operators, most notably, someone operating a sports book, via online, out of the state. Of course, such operation was also a violation of Federal law which, pending a Supreme Court decision, renders illegal any sports booking/betting activity with exception to only a few states.
The majority of online casinos will accept players from Alabama for this reason. Given that they are licensed by and operate out of jurisdictions that have nothing to do with the United States, they are legally untouchable by U.S. or state authorities.
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