An oath is a public pledge that a person will perform some action or duty, generally with the promise of doing so truthfully. An oath can also be used as a way of promising oneself to support a cause or an entity. Oaths are often done in the name of a deity–like swearing “under God”–though this is not always the case.
Today, oaths are required in many circumstances. In the legal system, a person must make an oath or affirmation that they will testify truthfully, also called a witness oath. This oath usually includes raising a person’s hand and promising that the person will tell “the truth, the whole truth, and nothing but truth.” This is often accompanied by placing a hand on a religious text. An example of this oath for Minnesota No-Fault Arbitration proceedings can be found here. Failure to tell the truth after swearing to do so–if done knowingly–results in the crime of perjury.
Those who wish to become naturalized citizens of a country are required to take an oath of allegiance or oath of citizenship. In the United States, this is governed by 8 U.S. Code § 1448 which states that all applicants must promise to uphold and support the Constitution, renounce any connection to a foreign entity, and swear allegiance to and defend the United States.
Some professions also require that those entering it swear an oath. These professional oaths usually promise that the person will perform their duties honestly, safely, and with integrity. For example, healthcare professionals are required to take the Hippocratic Oath. Generally, there are no actual punishments attached for breaking a professional oath itself. However, actions that are not in accordance with a professional oath can often constitute malpractice and can lead to lawsuits or even removal from the profession.
All individuals who are elected or appointed to a public office are required to take an oath of office. For the President of the United States, this is governed by Article II, Section 1, Clause 8 of the Constitution. For other offices–especially the U.S. House of Representatives, the Senate, and the Supreme Court–this is governed by 5 U.S. Code § 3331.
[Last updated in July of 2020 by the Wex Definitions Team]