How did the grandfather clause, which was enacted in southern states during reconstruction, stop certain races of people from voting? at least one member of a family had to own land to vote, but many blacks did not own land. therefore, the vote was heavily decided by white citizens. the head of household of a family had to sign up family members to vote. many head of households of black families were illiterate, so they were unable to read the paperwork necessary to register for voting. citizens had to pass literacy tests to vote, but those who had ancestors who were eligible to vote were exempt from tests. this meant many blacks could not vote because they could not read and only had ancestors who were slaves and who therefore were ineligible to vote. all citizens were required to provide documentation to vote. whites already had access to official documents, having been citizens since birth, while blacks had to apply for and purchase documents. this was a long and difficult process that limited their access to voting.