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In the United States, the Congress is prohibited from passing ex post facto laws by clause 3 of Article I, Section 9 of the United States Constitution. The states are prohibited from passing ex post facto laws by clause 1 of Article I, Section 10. This is one of the relatively few restrictions that the United States Constitution made to both the power of the federal and state governments before the Fourteenth Amendment. Over the years, when deciding ex post facto cases, the United States Supreme Court has referred repeatedly to its ruling in Calder v. Bull, in which Justice Samuel Chase held that the prohibition applied only to criminal matters, not civil matters, and established four categories of unconstitutional ex post facto laws.[20] The case dealt with the Article I, Section 10, prohibition on ex post facto laws, because it concerned a Connecticut state law.