By the Bais Hora'ah
Q. Reuven hired a painter to repaint the porch of his summer home in the Catskills. No one was in the colony to confirm which house was Reuven’s, and the painter mistakenly painted Shimon’s porch instead. The painter left an invoice for his work, but Shimon says that since he didn’t hire the painter, he should not be required to pay.
Is Shimon correct?
A. Chazal taught (Bava Metzia 101a) that a person is required to compensate someone who provided him a service that brought him some sort of benefit, even if he never requested that service. Therefore, if a person plants trees in someone else’s field without permission, although what he did was incorrect (Teshuvas HaGeonim, Chemdah Genuzah 40), if the field was supposed to be planted with trees, the owner is required to pay him the local wage for such work. If the field was not supposed to be planted with trees, but the value of the field rose because of the trees, he is only required to cover the costs of the raw materials used to do the work, [in addition to the minimum hourly wage in that locale (Shach 306:5)]. If the rise in value of the field is less than the price of the raw materials, the owner is required to pay only for the actual difference in value, which is the amount he benefited, not for the outlay invested by the person who planted the trees (Shulchan Aruch Choshen Mishpat 375:1, with Minchas Pittim).
Applying this principle to our case, Shimon certainly isn’t required to pay the full price of the painter’s work, but he is likely to have to pay the value of having his porch freshly painted. This amount is difficult to estimate, so in most cases, the two parties will have to agree on some sort of compromise.
If Shimon was planning to hire a painter to paint his porch anyway, he is required to pay the going rate for this work. If the paint job was done at a higher level, but Shimon was not planning to pay for the more expensive method, we cannot obligate him to pay more than he intended to pay for the job.
Even if Shimon claims that he had no interest in repainting his porch, beis din will estimate how much a person would be willing to pay to have a freshly painted porch rather than a worn one, because in most cases, for the right price, a person would agree to have his porch repainted. Similarly ,if the painter used superior materials, we can assume that had Shimon been offered these better materials for the right price, he would likely have agreed to pay for it, so he has to pay the amount he would have agreed to pay to have that level of work done.
Again, since it is difficult to estimate, in hindsight, how much a person would have been willing to pay for this work, the two sides will have to compromise.
If Shimon was planning on doing the repainting himself, he is required to pay for the materials and for the minimal amount he would be willing to pay to have someone else do the work (Choshen Mishpat 375:4).
There is another precedent in halachah that we must consider. In the case of the field, if the owner claims he had no interest in investing in this field at all at this point, he can tell the person who planted to uproot the trees and remove them (ibid. 375:2 and 6; Sma 4) – unless it is obvious that in truth, he wants the work done, and is merely trying to force the one who did it to compromise for a lower price, in which case we require him to pay (ibid. Sma 13).
In our case, there is no way for the painter to undo his work, and if he does, he won't be able to recover the paint he used. Some rule that in such a case, the owner cannot say, “Remove what you did” (Nesivos 306:7 and 375:2), so he must pay for the benefit he derived. Others say that this is only true if it was supposed to be painted and it is obvious that he isn't sincere when he instructs the worker to undo his work, and is merely seeking to absolve himself from paying. Therefore, if the owner had no intention of painting, he can certainly absolve himself by claiming that he is not interested in keeping the benefit (Minchas Pittim).
Many poskim rule, however, that even in a case in which the work cannot be undone, beis din should determine whether Shimon benefited from the work he didn’t commission, in which case we require him to pay for that benefit, or if he had no need for it at all, in which case he is absolved from payment (Erech Lechem 375:6; Chazon Ish Bava Kamma 22:6 and Bava Basra 2:6).