 Like all U.S. states' constitutions, the California Constitution adhered closely to the format and government roles set up in the original 1789 U.S. Constitution—differing mainly in details.The Constitutional Convention met for 43 days debating and writing the first California Constitution.The 1849 Constitution copied (with revisions) a lot out of the Ohio and New York Constitutions but had parts that were originally several different state constitutions as well as original material.