[Sacajaweau]

I doubt it is admissable UNLESS it was an admitted "false accusation".

[Law is not justice but process]

I would think that if the defense had clear and convincing evidence the prior accusation was false, they might bring it in, as it would be highly probative of credibility. If, for instance, the case was not pursued because the accused were, say, in the Army and stationed in Germany at the time of the accusation, the defense could probably get it in. It is a collateral matter (and judges who aren't named Ito hate collateral matters), but it would be so cotton-pickin' probative of credibility I think it would HAVE to come in.