Where the Court finds that the public authority had exceeded its jurisdiction or had exercised its discretion wrongly, it may strike down the decision on the basis of illegality. A decision-maker is said to be acting "ultra vires" (beyond its powers) when it does not have the power it purported to have, and therefore there is no basis in law for the impugned action or decision. The ground of judicial review is termed "simple" to distinguish it from a broader conception of "ultra vires" developed by the courts that was referred to earlier, which essentially encompasses all the forms of illegality mentioned in the rest of this article. As simple "ultra vires" concerns the exact powers conferred upon government ministers and statutory bodies, statutory interpretation is arguably the most important exercise the courts need to engage in to determine the scope of powers laid out in the statute. Hence, the cases decided are fact-specific and depend upon each court's interpretation of the relevant statute, making success of the judicial review somewhat unpredictable. The UK case of "Attorney General v. Fulham Corporation" (1921), illustrates this concept. The defendant was a statutory body establishing washhouses and baths for residents who could not afford their own washing facilities. When it subsequently established a laundry service, the defendant was declared to have acted "ultra vires" since its statutory purpose was not to carry on a business. Even though the business was carried out at a substantial loss, the statute in question did not give the defendant such a power to do so. Accordingly, the plaintiff was entitled to succeed. (Bancoult) v. Secretary of State for Foreign and Commonwealth Affairs" (2000), was a case concerning the forcible removal of the indigenous people of the Chagos Archipelago from Diego Garcia and the prohibition of their return by the Government of the United Kingdom so that the United States could construct a large military base there. This was effected by section 4 of the Immigration Ordinance 1971 of the British Indian Ocean Territory enacted pursuant to section 11(1) of the British Indian Ocean Territory Order, which states: "The Commissioner [for the British Indian Ocean Territory] may make laws for the peace, order and good government of the Territory, and such laws shall be published in such manner as the Commissioner may direct." The High Court held that the 1971 Ordinance was "ultra vires" the Order, since removing a people from their homeland could not be regarded as within the power to make laws for the territory's "peace, order and good government".