I know in at least one court case the police lost due to not responding in a timely mannor and it turned out that it was due to differences in the clocks. This was the reason the company I worked for at the time incorporated time synching into all their e911 products because after that it became a requirement. So I know someone has won against the .gov in thet respect.
I could see not being able to make a case against a resturant or business which has posted a no waepons sign on the door or even against the airlines since you could choose to not enter the building or get on the plane. But in the case where the government forces an evacuation and then forces you to become defenseless you don't have that choice.