One way African Americans were deprived of their right to vote was through the use of poll taxes. A poll tax was a payment a person would have to make in order to vote. African Americans were the poorest members of society so many could not afford this tax. Another way African Americans were deprived of their right to vote was through literacy tests. A person would have to show that he could read and write in order to vote. African Americans were the least educated members of society so many could not pass this test. Many times these tests were rigged so African Americans would fail them. To allow poor, illiterate whites to vote, grandfather clauses were passed which allowed anyone whose father or grandfather was eligible to vote before 1867 would not have to pay the tax or take the test. Since no African Americans were allowed to vote prior to the passage of the 15th Amendment in 1867, the grandfather clause would not apply to them, but would allow poor, illiterate whites to vote. Finally, organizations such as the Ku Klux Klan were established which used violence or the threat of violence to keep African Americans from voting.