Lil' Wayne was originally charged with possession, not "attempted possession." He admitted that he possessed the gun, and supposedly there was also DNA evidence to support the original charge. He plead to "attempted possession" in order to avoid a trial and get a lighter sentence.
Anyone think he couldn't have hired the best lawyers to fight it? Whether the law was just or not, he was guilty of "possession" but plead to attempted possession" in order to get a lighter sentence.
Under the law, "attempted (whatever crimminal act)" requires that the accused take some active/material step toward committing the act. [This does not hold true for "conspiracy" charges wherein only exchanged words are neccessary.]
Look at it this way; What if someone were caught with 50 lbs. of black powder, cannon fuse, the floor-plan of the parking garage garage at a shopping mall and a manifesto deriding America's "greedy capitalist society." No crime has been committed, so we should not charge the individual with anything? I suspect we wouldn't hear much of a hew & cry about his/her civil rights.
Admittedly, it is difficult to get into the mind of another, but a line must be drawn somewhere when possible crimes are discovered beforehand. Life does not always present us with black & white situations and the law must set limits somewhere.