It should be noted that although the ecclesiastical and secular rule and courts were separate, they were not mutually exclusive. In other words, it was possible for the church officials to hold secular titles with all the associated privileges and duties, effectively giving them ability to govern over both church matters according to their rank within their (arch)diocese and secular cases in their land. And save for their ecclesiastical office, they were in all regards secular lords, that had their own vassals and subjects and thus had to govern the economy of their land, attend to legal matters, hold court and mediate in potential conflicts just like any other noble landowner.

In addition, the title of the church official in question gives a big hint about the character of the case and possible motives of the plaintiffs, because the Archbishop of Mainz was definitely not an ordinary member of the ecclesiarchy. Between 1263 and 1803 Archbishops of Mainz also held the title of the Prince-Elector and their status among the Electors was elevated because they also held the position of the president of the Electoral Assembly and the Imperial Archchancellor of Germany. It might be thus argued that the Archbishop of Mainz was the most senior German Imperial official just after the Emperor himself.

It is worth noting, that since at least 1356, i.e. from the issuance of the Golden Bull by the Emperor Charles IV, and most likely even earlier, as the Bull generally formalized the existing customs rather than introduced them, Electors enjoyed the judicial autonomy, meaning that their legal decisions were final and could not have subjected to an appeal to the Imperial court or other Imperial officials. I do not known details of that particular 1438 case (the date might be significant as there was an outbreak of bubonic plague in Nuremberg a year earlier), but this is possible the people mentioned in the original decided to bring the matter to the Archchancellor to receive a definitive ruling. It was also possible that the matter in question was related to the land held or governed by Elector of Mainz and thus it was natural for him to preside over this particular matter. Or it could have been a different matter, as the same Archbishop of Mainz, Dietrich Schenk von Erbach, officially promised a protection for the Nuremberg merchants going to a 1436 Lenten fair in Frankfurt, even though neither of the cities nor the route inking them was largery not within the land held by the Archbishop. It would be good to have details, however, as Nuremberg was nominally a part of the Burgraviate of Nuremberg that since 1420 was a part of the Electorate of Brandenburg (although since 1427 is was politically independent in all matters related to the city itself), so the involvement of another Elector is interesting. Nevertheless, it is very possible that Archbishop of Mainz was involved in his capacity of a Prince Elector or an Archchancellor of Germany, not the one of an archbishop.