I came across a bit of legal dilemma set in late Georgian Period - and the last days of Bow Street Runners - regarding the heir or heiress of a wealthy aristocrat who suddenly decides to marry outside their social rank, and against his/her parents wishes. Were there legal grounds for the absconding lovers to be brought to heel? Could the Provost have jurisdiction in such a case, or would it have been resolved 'another way'? It's another matter if the runaway in question injured or stolen from somebody during their escapade, and the victim wished to press charges. But did the aristocracy have greater powers other than political influence?
I have no idea! Wickham got away with absconding with one of the Bennet daughters. I suspect if they reached Gretna Green then the parents were helpless? I suspect there was no law to kidnap an adult just because they were eloping with an unsatisfactory lover. A pistol might work though?