A common sense solution
A lot of ink (or pixels) has been spilled over Facebook's apparently knee-jerk reactions to Digital Millennium Copyright Act takedown notices that really are bogus.
But, slowly, common sense is beginning to creep into the digital world - in other words, a realization that all things don't work digitally (or free - but paywalls is a discussion for another day).
In this case, I found a quite common sense suggestion in the comment thread to the Tech Dirt discussion:
How stupid do you have to be to accept any sort of legal communication by email? Would you take down a site based on a Post-It Note™ stuck on your door, because they are about as secure as email.Amen.
When someone emails our organization with anything containing legaleese, DCMA, Etc, the mail server politely responds "It looks like this email contains material of a legal nature (relating to laws, trademarks, copyrights). Your email has NOT been delivered and is being returned to you because communications of this nature are not appropriate for an insecure medium such as email. If you have a legitimate concern please forward hand-signed documents by courier or registered mail. Thank you. Please be advised that your email WILL NOT be delivered"
If ISPs didn't make it so easy for people to abuse them they would make life much easier for everyone.