JACKSON, Miss. (AP) — The state of Mississippi has corrected a clerical error that left unrecorded ratification of the 13th Amendment for 18 years.

The Legislature formally ratified the amendment, which outlawed slavery, in 1995. However, the ratification document was never presented to the U.S. Archivist, so it was never official.

The Clarion-Ledger reports that on Jan. 30, Secretary of State Delbert Hosemann sent the Office of the Federal Register a copy of the 1995 Senate resolution, adopted by both the Mississippi Senate and House. On Feb. 7, Charles A. Barth, director of the Federal Register, wrote back that he had received the resolution and recorded the state’s action.

The newspaper reports the oversight was found by some Mississippians who after seeing the movie “Lincoln” looked up historical accounts of Mississippi’s action.