Everything on the internet is true

[Nystul]

I am willing to bet that a strict liability case agains Craigslist would win. We will see if Mr Fagan pursues that. What Craigslist allowed was a fraudulent act to be committed. Their disclaimer is no defense.

I wouldn't rule that out, but let's not forget some person wrote this ad. And it's probably not some hacker in China or Poland beyond the reach of the law; it is someone local who knows a horse exists at that specific address and probably has some sort of relationship to the owner.