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.
Right of foreigners to vote
(EU member) Municipal voting rights are granted to citizens of countries which reciprocate by granting voting rights to Spanish citizens when reciprocity is enshrined in a bilateral treaty ratified by Spain, i.e. since 1997 the EU member states and Norway, but already since 1989-1990 Denmark, the Netherlands, Sweden and Norway. Bilateral treaties with Argentina (1988), Chile (1990) and Uruguay (1992) have never been enacted as voting rights are not enshrined in a specific law in Chile, and for the two other countries the instruments of ratification have never been exchanged, there are also similar "friendship treaties" with Colombia and Venezuela. There is an ongoing debate in Spain about either ratifying existing bilateral treaties or changing the constitution in order to grant all residents voting rights without reciprocity, but some Catalan parties are opposed to it.