The case involves Calder and his wife suing Bull and his wife, but details are not provided. The Supreme Court of Errors of Connecticut affirmed the decree with costs. The Constitution of Connecticut allows the Legislature to grant new trials, which is considered constitutional as long as it does not conflict with the Constitution of the United States. The Legislature acted in both legislative and judicial capacities when awarding a new trial, but it is not considered an ex post facto law as it only applies to crimes and penalties, not civil cases. Some state constitutions prohibit ex post facto laws as they are considered unjust and oppressive.

Ex post facto laws only apply to penal statutes that create or enhance crimes, pains, and penalties. The prohibition of ex post facto laws in the US Constitution only refers to crimes, pains, and penalties. The author opposes retroactive laws but believes that ex post facto laws must be limited to their technical and common interpretation. The Connecticut Legislature has the power to grant new trials, which is consistent with their general supervisory authority over the state's courts. Some jurists argue that no court has the power to declare a legislative act void, even if it goes against natural justice.

Legislative power is restrained within constitutional boundaries to prevent abuse. The court cannot declare a law void if it is within the legislature's constitutional power, even if it goes against natural justice. The prohibition against ex post facto laws only applies to criminal cases, not civil cases. Penal dispensations have been used as a pretext for tyranny in Europe, so the framers of the American Constitutions denied legislatures the power to pass ex post facto laws. However, the prohibition does not apply to civil cases that affect private property. Necessary acts of legislation may require private rights to yield to public exigencies, but owners must be given reasonable compensation. The American government is one of the freest from danger in this respect.

The case involves an ex post facto law in criminal matters, but the objection does not apply because the act is not within the Constitution's prohibition. If the act is a judicial act, it is not affected by the Constitution, and if it is a legislative act, it is justified by the state of Connecticut's ancient and uniform practice. The judgment is affirmed.