Justice Stevens: Is Shakespeare Shakespeare?

Turns out Supreme Court justice John Paul Stevens is a huge Shakespeare buff - except he doesn't believe William Shakespeare wrote the plays attributed to his name. There are a few theories like this, each supporting a different person they think wrote Shakespeare's plays (Stevens believes the author was Edward de Vere, the 17th Earl of Oxford). Personally, I don't see the point in quibbling over whether Shakespeare was Shakespeare, and I find the evidence against to be wobbly at best. But apparently Justice Stevens has become one of the foremost experts on the issue. I'm just surprised a Supreme Court justice would have enough free time to become an expert on something else!