The fact that he told Bernard Shaw that he wouldn't retaliate if a thug raped his own wife pretty much sealed his fate.
He never said this!
To paraphrase the question, he responded, passionless, that he would not favor the death penalty for someone who raped and killed his wife.
That's kind of different than saying that he wouldn't retaliate.
It was an extremely unfair question, in my mind. Any candidate who didn't look shocked and then exclaim "I would have killed the bastard right there myself!" would have inevitably looked bad. Granted, Dukakis looked about as bad as anyone possibly could have in his response to the question, but I still maintain that it was extremely unfair. It would have been, quite simply, impossible for an anti-death penalty candidate to answer the question in a way that would not make him appear either as an uncompassionate monster or as an inconsistent waffler.