So Jammie Thomas-Rasset did indeed download and share music using P2P. Others have commented on the disproportionate nature of the penalty damages imposed in this case. Here I want to address a narrower question: how many copies should she be charged for?
The RIAA argues that Thomas-Rasset was sharing 1,700 audio files, and that 2.3 million P2P users had access to those files. This is "the equivalent of standing on a street corner with approximately 150 CDs and giving away free copies to anyone who asks".
But clearly Thomas-Rasset didn't actually create 2.3 million copies of those 1,700 files. Even if she had, the people who downloaded the files must share some responsibility, since they actively chose to make copies (unlike Thomas-Rasset, who merely chose to make them available). The RIAA seems to believe that because we don't know how many people actually downloaded these tracks from Thomas-Rasset's computer rather than someone else, that statutory damages are justified.
But this begs an important question: if a million people decide to share and copy some music track over P2P, how many copies do they make? The answer is quite obvious: one million users, one million copies. Nobody is going to fill their disks with thousands of copies of the same song, and even if they did it wouldn't make any difference.
(Actually quite a few users will have also made temporary copies on MP3 players and the like, but since doing that with a CD you own is fair use, that seems pretty irrelevant)
So at most Thomas-Rasset is guilty of having made 1,700 illegal copies of 1,700 songs. The fact that these songs were also available for others to download is irrelevant to the damages argument. Maybe 1,000 people made copies of these songs, maybe none. Civil law (which this is) is based on the balance of probabilities, and on the balance of probabilities the total responsibility of Thomas-Rasset for the copies made by the network of which she was a part is one copy of each song. These songs are sold for download for a dollar each, which suggests that, absent punitive damages, Thomas-Rasset's true liability should be $1,700. Even with triple damages for deliberate actions, that would still only be $5,100.
But of course, this isn't about justice for artists, this is about the business model of the RIAA members.