There's been a lot of speculation on whether or not families of the mall shooting victims have grounds to sue the mall. The mall prohibited civillians from carrying firearms on the premises, but one of the first things they did afterwards was remove the "gun free zone" signs. Whether it was for liability reasons or for a sence of black humor (the mall wasn't really gun free after all), the presence of these signs with legal bearing were obviously important to someone.
Sami Barrak got a 26 million dollar settlement from the mall where he was shot. He argued that the mall didn't take adequate measures to protect the safety of its costumers. Would this be a legal precedent to other suits? Mind that this was a settlement, not a court decision, although he was originally awarded more than a hundred million by a jury!
At any rate, it would be an interesting trial to watch.