The Tichborne case was a legal cause clbre that captivated Victorian England in the 1860s and 1870s. It concerned the claims by a man sometimes referred to as Thomas Castro or as Arthur Orton, but usually termed "the Claimant", to be the missing heir to the Tichborne baronetcy. He failed to convince the courts, was convicted of perjury and served a long prison sentence.

Roger Tichborne, heir to the family's title and fortunes, was presumed to have died in a shipwreck in 1854 at age 25. His mother clung to a belief that he might have survived, and after hearing rumours that he had made his way to Australia, she advertised extensively in Australian newspapers, offering a reward for information. In 1866, a Wagga Wagga butcher known as Thomas Castro came forward claiming to be Roger Tichborne. Although his manners and bearing were unrefined, he gathered support and travelled to England. He was instantly accepted by Lady Tichborne as her son, although other family members were dismissive and sought to expose him as an impostor.

During protracted enquiries before the case went to court in 1871, details emerged suggesting that the Claimant might be Arthur Orton, a butcher's son from Wapping in London, who had gone to sea as a boy and had last been heard of in Australia. After a civil court had rejected the Claimant's case, he was charged with perjury; while awaiting trial he campaigned throughout the country to gain popular support. In 1874, a criminal court jury decided that he was not Roger Tichborne and declared him to be Arthur Orton. Before passing a sentence of 14 years, the judge condemned the behaviour of the Claimant's counsel, Edward Kenealy, who was subsequently disbarred because of his conduct.

After the trial, Kenealy instigated a popular radical reform movement, the Magna Charta Association, which championed the Claimant's cause for some years. Kenealy was elected to Parliament in 1875 as a radical independent but was not an effective parliamentarian. The movement was in decline when the Claimant was released in 1884, and he had no dealings with it. In 1895, he confessed to being Orton, only to recant almost immediately. He lived generally in poverty for the rest of his life and was destitute at the time of his death in 1898. Although most commentators have accepted the court's view that the Claimant was Orton, some analysts believe that an element of doubt remains as to his true identity and that, conceivably, he was Roger Tichborne.

Perjury is the intentional act of swearing a false oath or falsifying an affirmation to tell the truth, whether spoken or in writing, concerning matters material to an official proceeding.Like most other crimes in the common law system, to be convicted of perjury one must have had the intention (mens rea) to commit the act and to have actually committed the act (actus reus). Further, statements that are facts cannot be considered perjury, even if they might arguably constitute an omission, and it is not perjury to lie about matters that are immaterial to the legal proceeding. Statements that entail an interpretation of fact are not perjury because people often draw inaccurate conclusions unwittingly or make honest mistakes without the intent to deceive. Individuals may have honest but mistaken beliefs about certain facts or their recollection may be inaccurate, or may have a different perception of what is the accurate way to state the truth. In some jurisdictions, no crime has occurred when a false statement is (intentionally or unintentionally) made while under oath or subject to penalty. Instead, criminal culpability attaches only at the instant the declarant falsely asserts the truth of statements (made or to be made) that are material to the outcome of the proceeding. For example, it is not perjury to lie about one's age except if age is a fact material to influencing the legal result, such as eligibility for old age retirement benefits or whether a person was of an age to have legal capacity.

Perjury is considered a serious offense, as it can be used to usurp the power of the courts, resulting in miscarriages of justice. In Canada, those who commits perjury are guilty of an indictable offence and liable to imprisonment for a term not exceeding fourteen years. Perjury is a statutory offence in England and Wales. A person convicted of perjury is liable to imprisonment for a term not exceeding seven years, or to a fine, or to both. In the United States, the general perjury statute under federal law classifies perjury as a felony and provides for a prison sentence of up to five years. The California Penal Code allows for perjury to be a capital offense in cases causing wrongful execution. Perjury which caused the wrongful execution of another or in the pursuit of causing the wrongful execution of another is respectively construed as murder or attempted murder, and is normally itself punishable by execution in countries that retain the death penalty. Perjury is considered a felony in most U.S. states as well as most Australian states. In Queensland, under Section 124 of the Queensland Criminal Code Act 1899, perjury is punishable by up to life in prison if it is committed to procure an innocent person for a crime that is punishable by life in prison. However, prosecutions for perjury are rare.In some countries such as France and Italy, suspects cannot be heard under oath or affirmation and so cannot commit perjury, regardless of what they say during their trial.The rules for perjury also apply when a person has made a statement under penalty of perjury even if the person has not been sworn or affirmed as a witness before an appropriate official. An example is the US income tax return, which, by law, must be signed as true and correct under penalty of perjury (see 26 U.S.C. § 6065). Federal tax law provides criminal penalties of up to three years in prison for violation of the tax return perjury statute. See: 26 U.S.C. § 7206(1)

In the United States, Kenya, Scotland and several other English-speaking Commonwealth nations, subornation of perjury, which is attempting to induce another person to commit perjury, is itself a crime.