I feel like you are supposed to be able to, or at least they should be the ones responsible. If you retweet something, then it is coming from a source that can be traced back. If in fact that source is not reporting something that is true then I feel like that should be on them. We're dealing in different times, but this is a the way I view it. Would it hold up in court? I don't know, I'm not a legal professional. 

If a trusted news site such as BBC or CNN tweets something compromising about someone, I ReTweet and after a few days, it turns out it wasn't true... am I equally responsible? Shouldn't I be able to trust those sites?

I would think at this point we can call social media a mature enough technology that would put it on the same legal grounds as other media. Books, magazines and newspapers all have to be vetted for legal ramifications. The digital world should be no different, especially when you consider traditional forms of media are slowly disappearing. 

With that being said, it's a scary thing to consider someone's mistakes or perhaps foolishness could end up very badly in a legal sense. Perhaps people need to be made aware of these risks that we are beginning to see. 

I read this: 

"Suggests that McAlpine's actions could expand the scope of libel actions in the UK by underlining the fact that statements on social media expose authors to the same liability as statements made in print -- in books, newspapers, or magazines."

I was wondering why that is not the case already. What makes social media immune?

slfisher, good point about eDiscovery.

But the legislation cited in the story you link to applies (I think) only to news organizations.  Journalists, working in their professional capacity, are protected from inadvertently retweeting something which turns out to be false.

Of course, "When is a citizen a journalist?" is another headache of a question the courts haven't yet really addressed.

"in the U.S. and it was determined that simply retweeting something that was libelous wasn't in and of itself libelous"

@slfisher - not so sure that one can re-tweet without being liable for libel.  I think libel requires that the injured party suffer some sort of harm due to defamation of character.  This could happen just as easily on a re-tweet as on a tweet.  If I tweeted something false about someone else, and Kim Kardassian retweeted it to her thousands of followers, I think she could be sued for libel.  I wouldn't have caused much damage to anyone's reputation tweeting to my five or so followers, but someone with a big following could inflict serious damage to someone's reputation by retweeting a falsehood.  In this case, I think the re-tweeter would likely get sued because they caused the most damage.

Didn't Spike Lee get into a bit of hot water recently for re-tweeting an address for a George Zimmerman in Miami?  I'm not sure if the original tweeter got in much trouble, but I heard it cost Spike Lee some serious cash.    

that this came up recently in the U.S. and it was determined that simply retweeting something that was libelous wasn't in and of itself libelous, though of course it's difficult to Google a reference to it now that every outlet is doing stories about the BBC aspect, though I did find this.

People also need to be aware of ediscovery aspects; Tweets and Facebook posts, as well as email, are subject to being discovered legally, and companies need to be aware of this and have a way to capture them quickly, completely, and cheaply.