The principal distinction between the terms “lawful” and “legal” is that the former contemplates the substance of law, the latter the form of law. To say of an act that it is “lawful” implies that it is authorized, sanctioned, or at any rate not forbidden, by law. To say that it is “legal” implies that it is done or performed in accordance with the forms and usages of law, or in a technical manner. In this sense “illegal” approaches the meaning of “invalid.” For example, a contract or will, executed without the required formalities, might be said to be invalid or illegal, but could not be described as unlawful. Further, the word “lawful” more clearly implies an ethical content than does “legal.” The latter goes no further than to denote compliance, with positive, technical, or formal rules; while the former usually imports a moral substance or ethical permissibility. A further distinction is that the word “legal” is used as the synonym of “constructive.” which “lawful” is not. Thus “legal fraud” is fraud implied or inferred by law, or made out by construction. “Lawful fraud” would be a contradiction of terms. Again, “legal” is used as the antithesis of “equitable.” Thus, we speak of “legal assets, “legal estate,” etc., but not of “lawful assets,” or “lawful estate.” But there are some connections in which the two words are used as exact equivalents. Thus, a “lawful” writ, warrant, or process is the same as a “legal” writ, warrant, or process.