In the 13th, 14th and 15th amendments it stated that there will be no slavery or involuntary servitude except in the case of punishment. All people born in the United States are citizens of America and no laws will be passed that will deny any person of life, liberty or property. In the 15th amendment it says that the right of a US citizen to vote will not be denied on account of race, color or previous condition of servitude.
