Landmark court decisions, in present-day common law legal systems, establish precedents that determine a significant new legal principle or concept, or otherwise substantially affect the interpretation of existing law. "Leading case" is commonly used in the United Kingdom and other Commonwealth jurisdictions instead of "landmark case", as used in the United States.[1][2]
In Commonwealth countries, a reported decision is said to be a leading decision when it has come to be generally regarded as settling the law of the question involved. In 1914, Canadian jurist Augustus Henry Frazer Lefroy said "a 'leading case' [is] one that settles the law upon some important point".[3]
A leading decision may settle the law in more than one way. It may do so by:
Distinguishing a new principle that refines a prior principle, thus departing from prior practice without violating the rule of stare decisis;
Establishing a "test" (that is, a measurable standard that can be applied by courts in future decisions), such as the Oakes test (in Canadian law) or the Bolam test (in English law).
Sometimes, with regard to a particular provision of a written constitution, only one court decision has been made. By necessity, until further rulings are made, this ruling is the leading case. For example, in Canada, "[t]he leading case on voting rights and electoral boundary readjustment is Carter. In fact, Carter is the only case of disputed electoral boundaries to have reached the Supreme Court."[4] The degree to which this kind of leading case can be said to have "settled" the law is less than in situations where many rulings have reaffirmed the same principle.
Amalgamated Society of Engineers v Adelaide Steamship Co. Ltd. (Engineers' Case) (1920): Rejected the doctrines of implied intergovernmental immunities and reserved State powers and determined that each head of federal power should be interpreted simply on the words of the grant.
In Commonwealth v Tasmania(Tasmanian Dams Case), the High Court held that the Commonwealth was able to invoke its external affairs power to give effect to Australia's obligations under international law, including to prevent the construction of the Franklin Dam in a World Heritage Zone.
Dietrich v The Queen, it was found that Australians accused of serious offences have a limited right to legal representation in order to guarantee a fair trial.
In Commonwealth v the ACT(Same-Sex Marriage Case) the High Court held that only the Commonwealth had the necessary legislative head of power to reform marriage laws to encompass same-sex marriage.
In Re Canavan(The Citizenship Seven Case), the High Court's earlier ruling in Sykes v Cleary was clarified and it was found that a dual citizen, irrespective of whether they knew about their citizenship status, will be disqualified from sitting in Parliament unless they are irremediably prevented by foreign law from renouncing their foreign citizenship as a result of the operation of s 44(i) of the Australian Constitution. 15 members of the 45th Parliament were either ruled ineligible to serve, or resigned on the basis of holding foreign citizenship.
There is no universally agreed-to list of "leading decisions" in Canada.
One indication, however, as to whether a case is widely regarded as being "leading" is its inclusion of the ruling in one or more of the series of compilations prepared over the years by various authors. One of the earlier examples is Augustus Henry Frazer Lefroy's Leading Cases in Canadian Constitutional Law, published in 1914. More recently, Peter H. Russell and a changing list of collaborators have published a series of books, including:
Leading Constitutional Decisions (first published 1965, with several later editions);
Federalism and the Charter: Leading Constitutional Decisions (published in 1989, co-edited by Russell, F.L. Morton and Rainer Knopff);
The Court and the Charter: Leading Cases (published in 2008, co-edited by Russell, Morton, Knopff, Thomas Bateman and Janet Hiebert); and
The Court and the Constitution: Leading Cases (published in 2008, co-edited by Russell, Morton, Knopff, Bateman and Hiebert).
Establishes that the Bill of Rights is not concerned with rights in any abstract sense, but rather with the more modest objective of prohibiting restrictions on rights as they existed in Canada at the time the Bill of Rights was enacted.
Status of English and French in Quebec legislation.
Established that all laws and regulations of the province of Quebec, as well as all courts and tribunals, must treat French and English with absolute equality.
Establishes that laws which impose prison sentences for "absolute liability" offences (i.e. offences for which intent or negligence need not be shown) are invalidated by section 7 of the Charter.
Establishes that section 7 does not mandate positive rights to welfare benefits, but that "a positive obligation to sustain life, liberty or security of the person may be made out" under different circumstances than those of the instant case.
Establishes that Charter-mandated rights come into existence, for purposes of applicability, only from the moment that their existence is determined by the court. Charter rights are not "discovered" in the sense proposed by Blackstone, and therefore are not retroactive.
The Supreme Court of India, which is the highest judicial body in India, has decided many leading cases of Constitutional jurisprudence, establishing Constitution Benches for hearing the same. Given below are a list of some leading cases:
Three Judges Cases (in which the Court established precedent regarding appointment of judges while ensuring absolute independence of the judiciary from the Legislature and the Executive):
S.P. Gupta v. Union of India & Anr. (Transfer Case (civil) 19 of 1981; 1982 2 SCR 365)
Supreme Court Advocates-on-Record Association & Anr. v. Union of India (W.P. (C) 1303 of 1987)
A-G v De Keyser's Royal Hotel Ltd [1920] A.C 508: establishing that the Crown has no right under the royal prerogative to take possession of an owner's land in connection with the defence of the realm without paying compensation, and that a statute in force may prevail to regulate the exercise of an existing prerogative power.
Ramsay v IRC [1982] A. C. 300: establishing a doctrine that ignores "for" tax purposes the purported effect of a pre-ordained series of transactions into which there are inserted steps that have no (commercial purpose) apart from the avoidance of a liability to tax.
Furniss v Dawson [1984] A.C. 474: establishing that tax can be levied on the results of a composite transaction, even if steps that are only there for the purpose of avoiding tax (do not) cancel each other out.
R (Miller) v Secretary of State for Exiting the European Union: [2017] UKSC 5: The Government may not use prerogative powers to undertake action that would remove rights previously granted under primary legislation, and instead must introduce primary legislation to undertake such an action.
Landmark cases in the United States come most frequently (but not exclusively) from the Supreme Court of the United States. United States Courts of Appeals may also make such decisions, particularly if the Supreme Court chooses not to review the case, or adopts the holding of the court below. Although many cases from state supreme courts are significant in developing the law of that state, only a few are so revolutionary that they announce standards that many other state courts then choose to follow.
