At law

According to law; by, for, or in the law, as in the professional title attorney at law. Within or arising from the traditions of the Common Law as opposed to Equity, the system of law that developed alongside the common law and emphasized fairness and justice rather than enforcement of technical rules.

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AT LAW. This phrase is used to point out that a thing is to be done according to the course of the common law; it is distinguished from a proceeding in equity.
     2. In many cases when there is no remedy at law, one will be afforded in equity. See 3 Bouv. Inst. n. 2411.