Hang on a minute. Before we get to that, do you now believe that there is evidence to support the claim that " "Rudy and Amanda smoked dope together on several occasions", or do you believe that there is not evidence to support this claim?
If you believe there is evidence, what is it?
If you do not, can you at least acknowledge that on this one point we were right, you were wrong, the text you claimed as evidence was not in fact evidence, and that "the citation game" you dismiss has a vital role in keeping people honest?
"Know" is not the most precise word in the English language, but it implies a degree of familiarity. If you have only ever met Andy Smith once very briefly at a party you wouldn't say "I know Andy Smith".
Amanda was introduced to Rudy once at a party, and that's as far as the evidence goes. Many people I have been introduced to at parties I would not say I know. Despite there being obvious media interest and police interest in the topic no further evidence of familiarity between Rudy and Amanda has ever emerged - the boys from the cottage below have not claimed Amanda knew Rudy, for example, and you would think they would know.
I think the likelihood that there is sooper sekrit evidence proving Amanda knew Rudy is about the same as the likelihood of the other sooper sekrit evidence known only to those present in court on the day proving Amanda was guilty existing. Which is to say, I think it's very highly unlikely and I put the idea down to wishful thinking.
I wouldn't have the least hesitation in saying , "Sure. I know Andy Smith. I met him at that party." Nor would I look askance at any other native English speaker who said something similar.
Now what? I understand that there are differences between American and Australian English, but I don't think that this is among them.
If it turned out that I could also add, "Yeah, I've run into him down at the bar I work at, and seen him around the basketball courts." then the usage is even less questionable. Not that there is any real question to begin with.
If you want to probe more deeply into
how well I might know him then that might be a different and more extended conversation.
One could just as easily be asked, "Do you know that chick at the supermarket check-out with the Farrah Fawcett hairdo and the
gazumbas out to
here!?" The response might be, "Yeah! She's
hawt, isn't she?", or maybe, "No, but I sure would like to!", which would also indicate familiarity.
You might want to pow-wow with Mary_H about the pedantry thing. This usage of 'to know' is quite common, completely acceptable, and indicates that someone is familiar with the individual in question.
This is in contrast to the statement, "I don't know him", which in common parlance suggests that the respondent would not recognize such an individual out of a group.
We usually don't assume that it is meant in the 'biblical' sense, or even kissin' cousins.