This article refers to Patricia Pulling and her Bothered About Dungeons and Dragons organization and it refers to Sean (not Shawn) Sellers' supposedly D&D-influenced killings.
Fortunately, Michael Stackpole has already done the work of investigating both of these, and you can look at The Pulling Report at http://www.rpg.net/252/quellen/stackpole/pulling_report.html (it's at other locations, too).
He does a fine job of dissecting her testimony, her book, her qualifications, and her knowledge of role-playing games.
Interestingly, her testimony in the Sean Sellers case as discarded. (You might want to look at Appendix 1 of The Pulling Report, where he reproduces a letter from Sean Sellers. Sellers states that Satanism, not D&D, was the decisive factor in his crimes.
For a different view on what Sellers did, I quote a police officer with the Vancouver Metropolitan Police, from http://www.conectionsjournal.com/files/archives/interviews/kerr.html :
"Sean Sellers is the youngest inmate on Death Row in California. he is allegedly 'Born Again' and
allegedly formerly a Satanist who became that way by playing Fantasy Role Playing Games. In fact,
he says that he killed somebody during a ritual, a Ritual Sacrifice. What he did was he walked into a
convenience store and shot the clerk dead in the course of a robbery, and now, to save his ass, he's
saying it was a ritual."
Of course, none of this is going to convince someone whose worldview is limited to, "If it's not God, it must be Satan!"
Of course, what I'd like to do is find evidence of the Israelites performing something like roleplaying in the old testament...