European styles of dueling established themselves in the colonies of European states in North America. Duels were to challenge someone over a woman or to defend one's honor. In the US, dueling was used to deal with political differences and disputes and was the subject of an unsuccessful amendment to the United States Constitution in 1838. It was fairly common for politicians at that time in the United States to end disputes through duels, such as the Burr–Hamilton duel and the Jackson-Dickinson duel. Dueling had become outdated in the north since the early-19th century. Dueling in the US was not uncommon in the south and west, even after 1859, when 18 states outlawed it, but it became a thing of the past in the United States by the start of the 20th century. To this day, anyone sworn into any statewide or county office or judgeship in Kentucky must declare under oath that he or she has not participated in, acted as a second or otherwise assisted in a duel.