There are two different aspects to these hidden compartment laws. One is charging you with a crime, the other is seizure of your property. The Feds can seize any vehicle with a hidden compartment, but you'll just lose your property in the seizure because there is no Federal law against hidden compartments. Seizure without due process is just theft, plain and simple, and it's been going on for years. According to the FBI:
Investigators also may seize a vehicle containing a hide.
Unfortunately, the legal tools available in charging cases involving hidden compartments are fairly limited. There is no federal statute specifically addressing the design, manufacture, or use of a trap, or, in the slang, clavo. Instead, charges at the federal level must be addressed through a statute dealing with drug paraphernalia.
IOW, any hidden compartment.Second, the drug paraphernalia definition contains only one reference to a category that could be construed as covering a hidden trap: "Any equipment...which is primarily intended or designed for use in...concealing...a controlled substance, the possession of which is unlawful."