The term case, whose etymological origin is found in the Latin casus, refers to a matter, an event or a fact. Fortuitous, meanwhile, is something that happens by chance, unforeseen or random.
The idea of fortuitous event, in this framework, is used with respect to what is produced by chance. Many times the expression refers to an event that causes damage and whose origin cannot be attributed to someone in particular.
In the field of law, according to DigoPaul, a fortuitous event is an event that the individual generates involuntarily and, therefore, is not expected to comply with certain obligations. In other words: a fortuitous event occurs when an event makes it impossible to fulfill an obligation, since that event could not be foreseen and, for that reason, could not be avoided.
In the legal ladder, the fortuitous event happens to the case of force majeure, which is one that not only could not be foreseen, but also, if it had been foreseen, it could not have been avoided either. Even with these differences, both cases are usually treated in a similar way by law.
Fortuitous events are unpredictable; cases of force majeure, unavoidable. It is often said that the fortuitous event is generated by a matter of internal order, while the case of force majeure comes from the outside.
Continuing with this differentiation, the fortuitous event occurs because of something that was unknown to the individual, although it was part of the internal plane of his action. The case of force majeure, on the other hand, is caused by an external event.
A mechanical failure in an automobile for which the cause is unknown is a fortuitous event. A tornado causing damage to a home, on the other hand, is a force majeure event.
In the two examples presented in the previous paragraph, one of the nuances on which the courts are based to resolve cases where it is impossible to blame someone directly can be seen: although we cannot perceive it with the naked eye, a mechanical failure inevitably arises from one or more errors (unforeseen in the best of cases) on the part of the technicians involved in the manufacture and, later, the maintenance of the car; it is the consequence of the way in which someone carries out their activity at a given time.
For this reason, as mechanical failure derives from the actions of a person and not from the effects of a natural phenomenon, we can decide that it is a fortuitous event. At the other extreme we find the case of the tornado that has left a house in ruins: if we apply what has been said so far, there is no doubt that it is a case of force majeure.
The backbone of the fortuitous event is made up of a series of characteristics that help us distinguish it from the others: it is unpredictable, unlike certain phenomena of nature; it is foreign to the debtor, so that the latter cannot have caused it voluntarily; it must arise after the cause of the obligation; it must harm the debtor directly; the debtor cannot fulfill the obligation.
As is often the case in this area, the characteristics of the concept are not identical in all countries, although we can broadly recognize it in all the laws of the world.
If we focus on the laws of Nicaragua, for example, we find a point of view according to which the fortuitous event and that of force majeure produce the same result, although the former is closely related to a series of events caused by humans (Although it does not generate them directly but rather they arise as collateral damage), while the second arises as a consequence of the action of nature.