The word locus (plural loci) is Latin for "place". “Locus standi” is Latin for ‘place to stand’- In law, the right to bring an action.
It is the ability of a party to demonstrate to the court sufficient connection to and harm from the law or action challenged to support that party's participation in the case. In United States law, the Supreme Court of the United States has stated -In essence the question of locus standi is whether the litigant is entitled to have the court decide the merits of the dispute or of particular issues.
There are three constitutional standing requirements:
Injury: The plaintiff must have suffered or imminently will suffer injury - an invasion of a legally protected interest which is concrete and particularized. The injury must be actual or imminent, distinct and palpable, not abstract. This injury could be economic as well as non-economic.
Causation: There must be a causal connection between the injury and the conduct complained of, so that the injury is fairly traceable to the challenged action of the defendant and not the result of the independent action of some third party who is not before the court.
Redress ability: It must be likely, as opposed to merely speculative, that a favorable court decision will redress the injury.
