> That seems like a clear example of destruction of evidence
If he was under arrest, sure. The cops claiming this was a routine airport inspection would seem to muddy the waters, at least.
Under Georgia law (16-10-94) you do not have to be under arrest.
> A person commits the offense of tampering with evidence when, with the intent to prevent the apprehension or cause the wrongful apprehension of any person or to obstruct the prosecution or defense of any person, he knowingly destroys, alters, conceals, or disguises physical evidence or makes, devises, prepares, or plants false evidence
I don't think the crime of destroying evidence / tampering with evidence depends on what your status in custody is. If the police knock on your front door and you start shredding documents, that's still a crime.
Now, could that get tossed about because they denied him access to a lawyer? Maybe, I don't know about that part.