Because he detested slavery and because tax revenues contributed to the support of it, Thoreau decided to become a tax rebel. There were no income taxes at that time and Thoreau did not own enough land to worry about property taxes; but there was the hated poll tax – a capital tax levied equally on all adults within a community. Thoreau was jailed in 1846 for refusing to pay taxes in protest against slavery and for publicly condemning the U.S. invasion and occupation of Mexico.