Someone who has met the legal definition of standing, that is someone who has suffered an injury in fact; an invasion of their legally protected interest that is concrete and actual, or imminent, and which is not conjectural or hypothetical. That injury in fact must have been caused by the actions of the defendant, and it has to be a matter that can be redressed by favorable decision of the court. Any federal court would have jurisdiction so long as the plaintiff is not seeking a writ of quo warrento, which requires the person to whom it is directed to show what authority he has for exercising his office. Only the United States can seek such a writ, unless the case if filed in a D.C. court.
That pretty much sums it up.
I always thought that quo warranto is the best route to go and it makes sense that jurisdiction be in the DC District Court since that is the seat of government and where the federal officers and offices are located.
This would be similar to filing lawsuits against a state in the county where the capitol is located.