I’ve blogged a bit over the years about the constitutionality of exclusive jurisdiction. That is, how can Congress divest state courts of jurisdiction over federal causes of action, such as antitrust. The Court has held that Congress can force state courts to hear federal courts of action (which does not create any commandeering problems). But under what power can the Congress tell a state court they cannot maintain jurisdiction.
Professor Amanada Frost two possible explanations. First, divesting state courts is a necessary and proper incident of their power to create inferior tribunals. That is, ensuring that only the district courts have original jurisdiction would require the states not having the jurisdiction. Second, it is a necessary and proper incident of the substantive law. In other words, in order for antitrust law to work properly, only federal courts can hear these cases. State courts having concurrent jurisdiction can frustrate the intent of Congress to regulate commerce through enforcing the antitrust laws. Another thought.