The prison’s rationale for the ban is that playing D&D might stimulate “gang activity” by inmates. But the government conceded that there is no evidence that Dungeons and Dragons actually had stimulated gang activity in the past, either in this prison or elsewhere.
While I am willing to concede that Dungeons and Dragons may evolve in prison into something wholly unfamiliar to me (though there's no evidence that it has), fostering dangerous gang activity instead of... well, the exact opposite... the logic is sort of mind-bending (p. 16, Singer v. Raemisch; PDF):
He testified that D&D “could foster an inmate’s obsession with escaping from the real life, correctional environment,” placing both the legitimate penological goals of prison security and inmate rehabilitation in peril. The prison officials have thus proffered evidence that the policy prohibiting possession of D&D manuals, strategy guides, character novellas, and other related materials is rationally related to the goal of preventing susceptible inmates from embarking upon a dangerous escapist path; they have “demonstrate[d] that [they] could rationally have seen a connection between the policy” and their ultimate penological goals.
I don't know if I'm reading this right, but it would seem, reading between the lines of the decision, that Risk might actually withstand a challenge from a penal institution (I'm not a lawyer, though, so do not send prisoners strategy games without consulting one); presumably it reinforces the importance of government.
I don't ask Lady Liberty for much, but please, please let this go to the Supreme Court.