So a friend of mine showed me a Shulchan Aruch (C.M. 412:1 and 412:2) the other day (which is based on a gemara in Bava Kama). To paraphrase the relevant points of the original text:
In 412:1 it says that if Reuven places a barrel in a public domain and Shimon tripped and broke it - Shimon is exempt from paying damages.
In 412:2 it says that if Reuven places a barrel in a place where he is allowed to and Shimon tripped and broke it - Shimon is liable for the damages. However, if it is dark or the entire road was filled with barrels, Shimon is exempt.
Finally, if the entire road is filled with barrels to an extent where it's impossible to pass - even if Shimon broke it with his hands he is exempt.
My friend is trying to figure out if this Halacha can be applied to a modern day case. Suppose, Reuven double parks his car illegally on a street. Shimon who is behind him thinks he can squeeze by so he starts inching forward... Except: crunch! Shimon hits Reuven's car and damages it.
So can we say that this is the same case as one who placed his barrel (car) in such a way as it blocks the street? Would Shimon therefore be exempt as he is just trying to get thorugh? Or is there some reason that this case is different?