[Herman Cain] was then asked, “Have you ever been accused, sir, in your life of harassment by a woman?”
He breathed audibly, glared at the reporter and stayed silent for several seconds. After the question was repeated three times, he responded by asking the reporter, “Have you ever been accused of sexual harassment?”
This is why we have the phrase "no comment."
Certainly, allegations don't mean the guy did anything wrong, nor would the paying of a settlement (or two) mean he did anything wrong. These things aren't evidence. Nor is his response to the question above, which to be fair is something of a "gotcha" question although it isn't quite "when did you stop harassing women?" "No comment" may not sound great, but it is the best of your bad options at that point, and is definitely better than glaring and then asking the reporter the same question back. So use it.
This is not the worst response to a difficult question we have seen, of course. That award is still firmly held by Florida state senator Gary Siplin, who in 2006 acknowledged he should have simply said "no comment" to reporters' questions about an indictment, rather than, say, suddenly sprinting out the back door of his office and scaling a chain-link fence to get away. This isn't evidence, either, but it just doesn't look good.
And as I said then, it's an especially bad strategy if you aren't quick enough to get over the fence before photographers reach the back yard.