A driver transferred a ride to his colleague and wants to pay him more than he received from the customer

Shalom,

A taxi driver was booked in advance for a certain ride that involved considerable effort, and he passed it on to another driver, his colleague. The first driver received the payment in advance and undertook to transfer it to the second driver. In practice, the first driver delayed and did not transfer the money to the second driver for a long time. Now the second driver is very upset with him, since the ride involved a great deal of trouble and was not really worth the price agreed upon in advance, and had he known how troublesome it would be, he would not have agreed to the ride. All the more so, he did not even receive the agreed price on time. Is it permissible for the first driver, who wishes to compensate the second driver, to pay him a higher amount, as many other drivers charge for such a ride?

Shalom u’vracha,

Given the combination of circumstances, one may be lenient and pay the higher amount as payment according to the market value of such a ride.

This leniency is based on several considerations. First, the obligation here is a debt arising through a transaction (chov derech mekach), since the first driver hired the second driver and undertook to pay him. (If the obligation had been only toward the passengers, and the first driver was merely safeguarding the money and acting as their agent to transfer it, then there would be no debt at all here, and the laws of interest [ribbit] would not apply.) Because of the delay in payment, this becomes a debt arising from a transaction, and interest on such a debt is rabbinically prohibited, as explained in siman 161, se’if 1. In this case, there is an additional reason on which to base the price increase:
the prevailing market price is the higher price. Although, according to the laws of hiring workers (sechirut po’alim), one cannot obligate the payer to give the higher price, since the amount was agreed upon in advance, and even if there was an error in the stipulated wage, we follow the lower end of the wage range, and there are workers who hire themselves out for the lower price, nevertheless, with regard to ribbit, since there is another reason for the higher payment, and it is possible that even without the delay he would have given him this amount in order to compensate him for his effort, this is considered interest at the time of repayment, which is permitted as ribbit derech mekach, provided he does not explicitly state that he is giving it in return for the wait (siman 160, se’if 4 in the Rema, and this is agreed to even by the Shulchan Aruch. It is explained in Taz there, se’if katan 3, and in R’ Akiva Eiger on the Shulchan Aruch there, se’if 6, that even if in his heart he thinks that he is giving it because of the delay, since he did not express it verbally, it is permitted. And if he “blends in” the addition, for example by giving four 50-shekel bills instead of three, he thereby satisfies the view of the Taz and the Perisha, who hold that even in the context of a loan this would be permitted in such a case). Another argument that can be added is that the extra amount he pays can be viewed as a form of penalty (knas). It is explained in siman 177, se’if 14 that this is not Torah-level ribbit, and according to the Rema, in ribbit derech mecher it is permitted if it does not increase (grow over time). It is possible that this depends on the underlying logic of the leniency regarding a penalty (see Bi’ur HaGra there).