A very small number of states, including Mississippi, still authorize civil lawsuits for "alienation of affections" in which a married person sued a third party who has sex or an affair with the married person's spouse.
So far, those lawsuits have not been held unconstitutional (despite the issue being cleanly presented to the U.S. Supreme Court for review if it wished to consider the issue), although the vast majority of U.S. states have abolished such lawsuits and it is a crime in Colorado to file, or seek to obtain a settlement of, such a claim.
But, what is someone from a state other than Mississippi that does not recognize an alienation of affects cause of action, in a place other than Mississippi that does not recognize an alienation of affections cause of action, has an affair with a married Mississippian and is sued by that married Mississippian's spouse. Can the spouse sue the "other man" or "other woman" in Mississippi for alienation of affections?
The Mississippi Supreme Court has ruled, 7-2, that he may, if the "other man" or "other woman" knew that the spouse was from Mississippi, but that he may not if the "other man" or "other woman" did not know that the spouse was from Mississippi.
This implicates a field of law known as "choice of laws". Historically, great emphasis was placed in both jurisdiction and choice of law, on the place that a critical fact was tied to, like the execution of a contract, or the place that a tortious act took place.
But, more recently, courts have looked to whether there are "significant connections" between the state whose law is to be applied (often the law of the forum state) and the events that took place. Hence, an automobile accident involving two people from Mississippi that takes place in California might be subject to Mississippi law rather than California law. Decisions like this one can flow from that approach and from the due process emphasis of the constitutional law of personal jurisdiction that requires someone to "purposefully avail themselves" of a state's laws by their actions in order to be subject to its jurisdiction.