Electoral system
Electoral rules place limits on suffrage and candidacy. Most countries's electorates are characterised by universal suffrage, but there are differences on the age at which people are allowed to vote, with the youngest being 16 and the oldest 21 (although voters must be 25 to vote in Senate elections in Italy). People may be disenfranchised for a range of reasons, such as being a serving prisoner, being declared bankrupt, having committed certain crimes or being a serving member of the armed forces. Similar limits are placed on candidacy (also known as passive suffrage), and in many cases the age limit for candidates is higher than the voting age. A total of 21 countries have compulsory voting, although in some there is an upper age limit on enforcement of the law. Many countries also have the none of the above option on their ballot papers.
Voter suppression
In the United States, elections are administered locally, and forms of voter suppression vary among jurisdictions. At the founding of the country, the right to vote in most states was limited to property-owning white males. Over time, the right to vote was formally granted to racial minorities, women, and youth. During the later 19th and early 20th centuries, Southern states passed Jim Crow laws to suppress poor and racial minority voters – such laws included poll taxes, literacy tests, and grandfather clauses. Most of these voter suppression tactics were made illegal after the enactment of the Voting Rights Act of 1965. In 2013, discriminatory voter ID laws arose following the Supreme Court's decision to strike down Section 4 of the Voting Rights Act, which some argue amount to voter suppression among African-Americans.