word | | Legal system |
| law | Tonga | English common law |
| law | Trinidad and Tobago | English common law; judicial review of legislative acts in the Supreme Court |
| law | Tunisia | mixed legal system of civil law, based on the French civil code, and Islamic law; some judicial review of legislative acts in the Supreme Court in joint session |
| law | Turkey | civil law system based on various European legal systems notably the Swiss civil code; note - member of the European Court of Human Rights (ECHR), although Turkey claims limited derogations on the ratified ... |
| law | Turkmenistan | civil law system with Islamic law influences |
| law | Turks and Caicos Islands | mixed legal system of English common law and civil law |
| law | Tuvalu | mixed legal system of English common law and local customary law |
| law | Uganda | mixed legal system of English common law and customary law |
| law | Ukraine | civil law system; judicial review of legislative acts |
| law | United Arab Emirates | mixed legal system of Islamic law and civil law |
| law | United Kingdom | common law system; has nonbinding judicial review of Acts of Parliament under the Human Rights Act of 1998 |
| law | United States | common law system based on English common law at the federal level; state legal systems based on common law except Louisiana, which is based on Napoleonic civil code; judicial review of legislative ... |
| law | Uruguay | civil law system based on the Spanish civil code |
| law | Uzbekistan | civil law system |