Why does Prima ban certain US states? What do they do to verify?

[Stark]

Anyone live in one of those states that had an account and still plays there? OR changed their address to another state and Prima didn't verify it, i.e. you could still cash out/deposit without them requesting some form of identification that proves you live in that state?

[Yakuman]

"The reason some operators have excluded certain sites and not the whole US population is because they are interpreting the law differently. The law addresses 'Unlawful Internet Gambling.' This means that the casino believes the states that had pre-existing law regarding online gambling are the states affected by this new law."
http://www.compatiblepoker.com/usa.php