Well, why would the police officer search your trunk? He would have no probable cause to unless you were drunk and had probably cause to search the car. If you're not drunk, have nothing in the main car, and he has no PC, then he can't search the trunk lawfully.
So, maybe you technically can't (i actually don't know. probably is state by state in the statutes), but it doesn't really matter.
Also, there's most likely some sort of exception to the general rule of open containers which allow for you not to be in violation if it's not within arm's reach, i.e., the trunk.
This post was edited on 5/12 at 10:44 am