FAULT

An improper act or omission which arises from ignorance, carelessness, or negligence. The act or omission must not have been meditated, and must have caused some injury to another.

Faults or negligence are usually divided into gross, ordinary, and slight:
    Gross fault or neglect consists in not observing that care towards others which a least attentive person usually takes of his own affairs. Such fault may, in some cases, afford a presumption of fraud and in very gross cases it approaches so near as to be almost undistinguishable from it, especially when the facts seem hardly consistent with an honest intention. But there may be a gross fault without fraud.
    Ordinary faults consist in the omission of that care which mankind generally pay to their own concerns; that is, the want of ordinary diligence.
    A slight fault consists in the want of that care which very attentive persons take of their own affairs. This fault assimilates itself and, in some cases, is scarcely distinguishable from mere accident or want of foresight. This division has been adopted by common lawyers from the civil law.

Different rules have been made as to the responsibilities of parties for their faults in relation to their contracts. E.G.:
    In those contracts where the party derives no benefit from his undertaking he is answerable only for his gross faults.
    In those contracts where the parties have a reciprocal interest, as in the contract of sale, they are responsible for ordinary neglect.
    In those contracts where the party receives the only advantage, as in the case of loan for use, he is answerable for his slight fault.
   

This entry contains material from Bouvier's Legal Dictionary, a work published in the 1850's.