Question
I was driving on a two-way street which has no place to park on the side of the road. In front of me was a car which was parked illegally partly on the sidewalk and partly on the street. In the opposite lane was a long line of cars and I would have had to wait at least a minute or two until everyone passed in order to drive normally past the illegally parked car. I thought that since I drive a small car that I could squeeze past the illegally parked car by driving slowly and carefully. However, even though I was driving very carefully, I was only partially successful since when I was almost through the gap, I slightly dented the illegally parked car. Am I liable for the damages?
Answer
Before answering your question, we must describe what transpired in legal terms. Since one is not allowed to park his car on the road, his car did not have permission to be where it was. You were driving on the road which is the proper thing to do. Thus, the place where you damaged his car was a place where you and your car were allowed to be and his car was not. We note further that since it was your direct action that damaged the parked car the damages fall into the category of odom hamazik. Your question then is whether odom hamazik is liable in your circumstances.
The Gemara (BK 48A) discusses odom hamazik in a situation where A entered B's property without permission. The amora Rava rules that if A damages B he is liable whereas if B damages A he is not liable. Rav Popo confines Rava's ruling about B to where B is unaware that A had entered. If B is aware that A entered, he is liable for damaging A even though A entered his property without his, the owner's, permission.
The Rishonim dispute when, according to R. Popo whose ruling is authoritative, B is liable for damaging A if B is aware that A is on his property. According to Rashi he is liable whenever he damages A by an action of his, whether he intends to damage A or not. However, the Rambam (Choveil U'mazik 6, 3) maintains that B is only liable if he intends to damage A. If he does not intend to damage A, he is not liable.
The Rambam goes beyond this Gemara and maintains that the rule is the same even if A and B were in a place where either both have permission or both do not have permission. Thus, he maintains that the only time B is liable for damaging A unintentionally is if the damage took place in A's, the victim's, property. This extension of the Rambam is rejected by most Rishonim and is not the consensus opinion.
However, if A entered B's property without B's permission, many major commentaries (Bach (378, 379), Yam Shel Shlomo (BK 5, 9), Machane Efraim (Choveil U'mazik 6, 5), Orach Hashulchan (378, 16), Chazon Ish (BK 4, 3, paragraph beg. mehu) maintain that others, including the Tur and the SA (378, 6) and the Yam Shel Shlomo (BK 5, 9) agree with the Rambam that B is only liable if he damaged A intentionally. (The Gro (378, 18) alters the text of the Tur and therefore, disagrees with this interpretation of the Tur.) According to these commentaries, SA cites the Rambam as the authoritative position and cites Rashi's approach as a non-authoritative position but worthy of mention.
There is another case of odom hamazik which is almost identical to your situation which is discussed by SA (CM 412, 2, and explained by Sema in comment 3). In this situation SA rules the approach of the Rambam without mentioning another position. The Rambam (Nizkei Momon 13, 6) discusses a person who placed his barrels in the public thoroughfare. He rules that if the barrels were placed in a manner that makes the thoroughfare totally impassible, a pedestrian may smash some of the barrels in order to clear a path. If one can cautiously traverse the thoroughfare, one may not purposely break any barrels. But if some barrels broke unintentionally the pedestrian is not liable.
The ruling that if the road is totally impassible a pedestrian may intentionally break some barrels is based on the Gemara (BK 28A) that explains that one may do so because of the principle that ovid enash dino lenafshei—a person may take the law into his own hands in some situations including this one.
However, this principle does not explain the ruling in case the road is not totally impassible. Moreover, the principle that ovid enash dino lenafshei cannot be the explanation since if that principle applies, according to the Gemara the pedestrian could intentionally break the barrels. Therefore, the correct explanation of the Rambam and SA is that this is another application of the Rambam's principle since in this case the barrels were illegally situated in the public thoroughfare and the pedestrian was properly traversing the public thoroughfare. Since the principle of the Rambam is that one is not liable for unintended damages but is liable for intended damages, he rules that if the pedestrian accidentally broke some of the barrels he is not liable, but if he did so intentionally he is liable. Since the other Rishonim do not discuss this case SA does not cite a dissenting opinion.
This latter case is exactly your case since the parked car is the equivalent of the barrels and you driving your car are equivalent to the pedestrian. Since you damaged his car accidentally, you are not liable.
We note that there are many situations where these principles apply. One situation is where a person drives in violation of the traffic rules and gets hit accidentally by someone who abided by the rules. Thus, the Mishpat Hamazik (vol. 1, 7, 3) writes that if A drives against traffic on a one-way street and is hit by B, who was not careless but miscalculated, these opinions absolve B from liability even though he saw A. Those like Rashi who disagree with the Rambam would only absolve B if he did not notice A.
Another case that is discussed by the Chashukei Chemed (BK 26A) concerns A who left his glasses on a bench in a beis hamedrash and B accidentally sat down on them. He writes that Rav Eliashev zatsal was inclined to rule that B is not liable since anyone may sit on a bench in a beis hamedrash, which means that he was acting properly. In this case the law should be that in places where people don't generally leave their glasses on a bench and people may sit on any unoccupied seat, if A initially noticed the glasses on the bench but then became so engrossed in his learning that he forgot that there were glasses on the bench and accidentally sat on them, he would not be liable according to the Rambam, Tur etc. since he damaged unintentionally and the glasses shouldn't have been on the bench. However, Rashi etc. would rule that A is liable since his action broke the glasses.
In conclusion: Since you damaged a car that had no right to be in a traffic lane unintentionally you are not liable. However, since there is an opinion that is cited by the SA that you are liable, if your victim seizes a possession of yours as payment for the damage, beis din would not force him to return it.