Exodus 21:32

32.If the ox shall push a man-servant. It is not unreasonable that the punishment for the death of a slave should now be set at less than for that of a free-man. As regarded the crime of voluntary murder, there was no distinction between slaves and masters; but in a case of mischance (delicto) the severity might in some degree be mitigated; especially when the stoning of the ox sufficiently availed for bringing murder into detestation. God, therefore, showed admirable moderation in condemning the negligence of the master to be punished by the payment of thirty shekels; whilst He proposed the ox as an example, and reminded all by its death, how very precious in His sight is human blood.