> there’s no reason why you wouldn’t be able to place drugs and guns in the trunk of the car
Most common drugs that people get busted with in their car (weed and alcohol) aren’t illegal on their own in most states, they are illegal in relation to the person driving the car. More specifically, could the driver even theoretically access those while driving later, without having to step out of the car? If yes, that’s illegal already, even if the person is fully sober.
For example, if I drive in California with a few joints in my trunk or a case of beer - totally legal. But if i am in the exact same situation, except the joints and the case of beer are in the cabin (even if it is in the backseat and is in fully-sealed original packaging that was provably never opened) - I am in trouble.
But the more serious barrier to this, as others have pointed out already, is that they cannot just pop your trunk to do anything shady with no probable cause. You can easily make up a probable cause that the driver looked impaired, even if that wasn’t the case, and then you can “inspect” the trunk and do whatever shady business you want. But a self-driving vehicle pretty much nullifies the possibility of that, because it eliminates sobriety of the person in the car from the equation.