MANDATE, in law, a term derived from the Roman civil law. It may be defined as a bailment (delivery) of a chattel or chattels to a person who is to do something with or about the things bailed, entirely without com pensation. The essential element of the con tract lies in the fact that there is not paid or promised, in law or in fact, any compensation whatever for the service to be rendered. The person delivering the chattels is called a man dator; and the person receiving them and un dertaking the service is called a mandatary. As it must he a service or an act, the whole benefit of which rests with the mandator, this, by the ordinary principles of bailment, deter mines the amount of care to which the man datary is bound, and the degree of negligence for which he is answerable. For negligence in a bailee has in law three degrees: slight neg ligence, which makes the bailee responsible where the bailment was wholly for his benefit: ordinary negligence, for which he is responsible if the bailment be for the benefit of both parties; and gross negligence, for which only the bailee is responsible where the contract is for the exclusive benefit of the bailor. And as it is not a mandate if the bailee derives any benefit whatever from the service, it follows that a mandatary is responsible for loss of or for injury to the thing delivered to him, only when it is caused by his gross negligence.
There is no especial form for the contract of mandate; it may be in writing or by word only, and made very solemnly or in the simplest way; in either case the law is the same. No man can be held in the United States for a breach of any promise, whether that breach be partial or total, if the promise rests upon no considera tion. But if he who has made a promise, after ward does some injury to the promisee (and this would be the case if he does something which is positively injurious because it is not completed), he is liable for the injury he has caused, as he would be if there were no prom ise between the parties. Banks and bankers are so far mandataries, that they receive notes for collection, and render, or engage to ren der, by agreement or by mercantile usage, these and similar services without any especial or specific compensation. But it is understood that they do this as a part of their business, and for the general and indirect benefit they derive from doing it; and this is undoubtedly consideration enough to make them liable for any injury to their customer caused by their negligence; and it is sufficient to make them liable that their negligence was ordinary, or consisted in the want of common care. And a bank has, as bailee, a lien on its deposits for i s general balance against the depositor.