I don't think that is correct. If you have more than $10,000.00 cash That you cannot explain I would think they could. I don't think even that is right, but I'll let the FR legal eagles chime in. Ive carried more than that to gun shows in cash and had no problems since I had my bank deliver it to me the day before the gunshow and I had a receipt and personal friendship and business relationship with the banker.
DC,
This is not a new law. 10 K if you get caught you MIGHT be able to get it back but I think it was created to help stop the underground economy. Not just drugs but all bog cash transactions.