Ray Beckerman updated his excellent discussion on how RIAA brings and conducts its lawsuits. It's a must read for attorneys and a helpful guide if you're the one being sued.

Here is the Introduction:

The RIAA lawsuits pit a small number of very large recording companies against individuals who have paid for an internet access account.

On the plaintiff's end, the owners of the underlying copyrights in the musical compositions are not involved in the case; neither are many smaller record companies.

As to the defendants, since no investigation is made to ascertain that the defendant is actually someone who engaged in Peer to Peer File Sharing of copyrighted music without authorization, there are many defendants who have no idea why they are being sued and who did nothing even arguably violative of anyone's copyright. Defendants have included people who have never even used a computer, and many people who although they have used a computer, have never engaged in any peer to peer file sharing.

Sometimes the cases are misleadingly referred to as cases against 'downloaders'; in fact the RIAA knows nothing of any downloading when it commences suit, and in many instances no downloading ever took place.

It is more accurate to refer to the cases as cases against persons who paid for internet access which the RIAA has reason to believe was used by some person -- possibly the defendant, possibly someone else -- to engage in peer to peer file sharing.