i don't get this declaring business - does it mean declaring you have more than $10k USD makes it legal? or does it just mean you've just confessed to a crime?
It's illegal to not declare if you have more than $10k USD when crossing borders. All the custom forms I have seen around the world have something along these lines, in various amounts and currencies.
That didn't really answer the question though. Is it a choice between "follow one law by confessing you broke another" vs. "break two laws and maybe not get caught"? Or is it a choice between "break one law" or "don't"?