Explanation:

Often someone wants another to believe something when they know there is no evidence for it. The reason there is no evidence for it is that it isn't true. That means saying it outright would be a lie. Instead, the technique of innuendo is employed to leave someone with the idea without actually stating it. The idea is that the receiver will assume or infer the suggested idea.

Examples:

(i) "Have you stopped beating your wife yet?" This suggests, without stating, that the person either still beats or used to beat his wife.

(ii) "Well, after all, he is a Southerner. We all know about them."

(iii) "Is John telling the truth?"
"Yes, this time." ("This time" suggests that he doesn't usually tell the truth.)

Proof:

Show that the person is implying something important without actually stating it or offering evidence for it.