Wikipedia on Jefferson's efforts against slavery--
Jefferson and slavery
Records show that Jefferson owned many slaves over his lifetime. Some find it hypocritical that Thomas Jefferson owned slaves yet was outspoken in saying that slavery was immoral and it should be abolished. In the Declaration of Independence, he states that " All men are created equal", yet he owned slaves himself.
During his long career in public office, Jefferson attempted numerous times to abolish or limit the advance of slavery. According to a biographer, Jefferson "believed that it was the responsibility of the state and society to free all slaves".[38] In 1769, as a member of the House of Burgesses, Jefferson proposed for that body to emancipate slaves in Virginia, but he was unsuccessful.[39] In his first draft of the Declaration of Independence (1776), Jefferson condemned the British crown for sponsoring the importation of slavery to the colonies, charging that the crown "has waged cruel war against human nature itself, violating its most sacred rights of life and liberty in the persons of a distant people who never offended him, captivating & carrying them into slavery in another hemisphere." However, this language was dropped from the Declaration at the request of delegates from South Carolina and Georgia.
In 1778, the legislature passed a bill he proposed to ban further importation of slaves into Virginia; although this did not bring complete emancipation, in his words, it "stopped the increase of the evil by importation, leaving to future efforts its final eradication." In 1784, Jefferson's draft of what became the Northwest Ordinance stipulated that "there shall be neither slavery nor involuntary servitude" in any of the new states admitted to the Union from the Northwest Territory.[40] In 1807, he signed a bill abolishing the slave trade.