From this we can see that there are two kinds of piracy--national piracy and municipal piracy. No State can be prevented by any law of nations from making anything piracy which that State pleases. For instance, there is a law of piracy in Spain that any person committing frauds in matters of insurance is a pirate; or that any one even cutting the nets of a simple fisherman is a pirate. I might quote other instances. In our own country the slave-trade is a piracy; but that does not make it piracy everywhere. In some of the States of Germany slave-trade is kidnapping, and is punished as such. What, now, is the relation of these foreigners to this municipal piracy, under the indictment with which they stand charged? That it is municipal piracy, I need not say anything further, after the full argument of our friend and father, Mr. Lord. The law is very distinct. It is, "if any _citizen_ shall do so and so." But how do these men come in? Here I come to the point why I thought it fit and incumbent on me to offer my propositions. The prosecution will certainly stretch, as I said before, the construction and interpretation of the law in this way: It will say, "These men were apprehended on an American bottom, and, being on an American bottom, they were on American soil, and as, according to criminal law, they are protected by our law, so they are bound by our law." This, I apprehend, is the theory on which the prosecution will urge that these foreigners--notwithstanding the distinct expression of the law, "if any citizen"--shall be found guilty under this indictment. But as they are foreigners to this law, so is this law foreign to them. And there is a principle in criminal law which says--I read from section 238 of Bishop's Criminal Law, vol. I.-- "It is a general principle that every man is presumed to know the laws of the country in which he dwells, or, if resident abroad, transacts business. And within certain limits, not clearly defined, this presumption is conclusive. Its conclusive character rests on considerations of public policy, and, of course, it cannot extend beyond this foundation, though we may not easily say, on the authorities, precisely how far the foundation of policy extends. We may safely, however, lay down the doctrine that in no case may one enter a Court of Justice to which he has been summoned, in either a civil or criminal proceeding, with the sole and naked defence that when he did the thing complained of he did not know of the existence of the law he violated. _Ignorantia juris non excusat_ is, therefore, a principle of our jurisprudence, as it is of the Roman, from which it is derived." This rule, so essential to the ordinary administration of justice, cannot be deemed strange in criminal cases generally, because most indictable wrongs are _mala in se_, and, therefore, offenders are still conscious of violating the law "written in every man's heart."