Calder v. Bull (1798)

1) Link to the Actual Opinion
Read the U.S. Reports opinion (PDF)

2) Summary of the Opinion
Connecticut allowed a new probate hearing. The challengers claimed it violated the Constitution’s ban on ex post facto laws. The Supreme Court held the Ex Post Facto Clause applies only to criminal laws, not civil ones.

3) Why It Mattered
This case clarified the scope of the Ex Post Facto Clause and featured a famous debate between Justices Chase and Iredell over natural law versus strict constitutional text.

4) What It Provided or Took Away

• Took Away: The ability to argue that retroactive civil laws are unconstitutional as “ex post facto.”

5) Overreach or Proper Role?
This was interpretive line-drawing consistent with the Court’s duty. It restrained the Clause to its textual intent.

6) Plain-English Impact Today
Retroactive criminal punishment is unconstitutional, but legislatures may sometimes pass retroactive civil laws (e.g., extending filing deadlines).

• Ex Post Facto
• Criminal Law
• Natural Law