The Lecompton Constitution was the second of four proposed constitutions for the state of Kansas (it was preceded by the Topeka Constitution and was followed by the Leavenworth and Wyandotte Constitutions, the Wyandotte becoming the Kansas state constitution). The document was written in response to the anti-slavery position of the 1855 Topeka Constitution of James H. Lane and other free-state advocates. The territorial legislature, consisting mostly of slave-owners, met at the designated capital of Lecompton in September 1857 to produce a rival document. Free-state supporters, who comprised a large majority of actual settlers, boycotted the vote. President James Buchanan's appointee as territorial governor of Kansas, Robert J. Walker, although a strong defender of slavery, opposed the blatant injustice of the Constitution and resigned rather than implement it. This new constitution enshrined slavery in the proposed state and protected the rights of slaveholders. In addition, the constitution provided for a referendum that allowed voters the choice of allowing more slaves to enter the territory.
Both the Topeka and Lecompton constitutions were placed before the people of the Kansas Territory for a vote, and both votes were boycotted by supporters of the opposing faction. In the case of Lecompton, however, the vote was boiled down to a single issue, expressed on the ballot as "Constitution with Slavery" v. "Constitution with no Slavery." But the "Constitution with no Slavery" clause would have not made Kansas a free state; it merely would have banned future importation of slaves into Kansas (something deemed by many as unenforceable). Boycotted by free-soilers, the referendum suffered from serious voting irregularities, with over half the 6,000 votes deemed fraudulent. Nevertheless, both it and the Topeka Constitution were sent to Washington for approval by Congress.
A vocal supporter of slaveholder rights, President Buchanan endorsed the Lecompton Constitution before Congress. While the president received the support of the Southern Democrats, many Northern Democrats, led by Stephen A. Douglas, sided with the Republicans in opposition to the constitution. Douglas was helped considerably by the work of Thomas Ewing Jr., a noted Kansas Free State politician and lawyer, who led a legislative investigation in Kansas to uncover the fraudulent voting ballots. A new referendum over the fate of the Lecompton Constitution was proposed, even though this would delay Kansas's admission to the Union. Furthermore, a new constitution, the anti-slavery Leavenworth Constitution, was already being drafted. On 4 January 1858, Kansas voters, having the opportunity to reject the constitution altogether in the referendum, overwhelmingly rejected the Lecompton proposal by a vote of 10,226 to 138. And in Washington, the Lecompton constitution was defeated by the federal House of Representatives in 1858. Though soundly defeated, debate over the proposed constitution had ripped apart the Democratic party. Kansas was admitted to the Union as a free state in 1861.
See also 
- Heller, Francis Howard, The Kansas State Constitution: A Reference Guide, Greenwood Press, 1992, pp. 1–4. ISBN 0-313-26510-0.
- Stampp, Kenneth M., America in 1857: A Nation on the Brink, Oxford University Press, 1992, pp. 167-80. ISBN 0-19-507481-5
- Flanagan, Mike, The Complete Idiot's Guide to the Old West, Alpha Books, 1999, p. 180. ISBN 0-02-862945-0
- "Key Events in the Presidency of James Buchanan". Miller Center of Public Affairs, University of Virginia. 2009. Retrieved July 17, 2009.
- Smith, Ronald D., Thomas Ewing Jr., Frontier Lawyer and Civil War General. Columbia:University of Missouri Press, 2008, ISBN 978-0-8262-1806-3.