"Those drugs aren't mine" is probably a common argument, and commonly unsuccessful.  And I would guess that it is an even tougher argument if you were found using a big bag of drugs as a mattress.

Customs agents have charged two men with conspiracy and possession with intent to distribute marijuana, after they found the men sleeping on top of large bundles of marijuana just east of Brownsville, Texas.  According to the complaint, agents spotted six sets of footprints in the desert at about 1 a.m. on September 27.  They eventually traced said footprints to "six men sleeping on top of six bundles of marijuana" near an intersection.  (The picture to the right is the Google street view of this charming area.)  That resulted in two arrests, and presumably four sets of footprints heading back out into the desert.

The complaint states that the two men who were arrested admitted that they had entered the U.S. illegally with the bundles, which they had taken turns carrying until they stopped to rest.  The report mentions six bundles and a seizure of "more than 350 pounds of marijuana," from which I conclude that each man got comfy on top of a 60-pound bag of pot.  Some of you may be able to visualize that better than I can, but it seems like it would be enough for each to have his own pot mattress.

Maybe next time they should use a less comfortable kind of marijuana, or put some small rocks in the bags.

Link: Brownsville Herald