During the past several months, we discussed many halachic aspects of minhag hamedinah, common commercial practice. To qualify as minhag hamedinah, the practice must be formally established by the community or widely accepted and a common occurrence.
In most contractual issues, when not stated otherwise, we assume that the parties implicitly operate according to the minhag hamedinah, even if not stipulated explicitly and in deviation from the default Torah law, especially in employer-employee issues.
In many cases, a civil law that is widely practiced can be considered binding among parties based on minhag hamedinah, even in cases where it might not be binding as dina d’malchusa. Transactions that are conducted in a manner widely accepted in that locale are usually binding even in the absence of a formal kinyan, as a form of kinyan situmta.
The application of minhag hamedinah in non-contractual issues, such as damages, is questionable.
Therefore, in adjudicating monetary manners, the Dayan must consider also the minhag hamedinah of his locale.
