You've hit on one of the most important issues. Police have a category for rape cases they're not going to continue investigating - a confusingly and misleadingly named category. In the US and Canada, it's "unfounded"; in the UK, it's "no crime". In all three countries, the category does *not* mean there actually wasn't a crime, or that there was no foundation for the report - it's just a bureaucratic label. Sometimes the police don't think the report is without foundation, or that no crime occurred - but as you suggest, don't think the case would have much chance in court, so still label it "unfounded" or "no crime" as though the report was a lie. Reports can also be "unfounded" for trivial reasons - I should put together a list.