Fans combing over every pixel of that new Barry Allen photo from Justice League have spotted what is almost certainly a comic book Easter egg on one of his computer screens.
One one of the screens, a largish bit of text reads "AC 301," likely a reference to Action Comics #301, given that "AC" stood in for "Action Comics" in preview Easter eggs on Batman v Superman: Dawn of Justice.
In the context of the DC Extended Universe, Superman has already been "on trial," at least sort of. He was summoned to speak before Congress in Batman v Superman, to address concerns about his role in a a rescue mission at the start of the movie, which seemed to have resulted in a bloodbath.
(In actuality, the casualties were all either outright falsified or the fault of LexCorp operatirves.)
Also in the movies, Clark Kent is currently dead.
In the comics, Superman's death was a fairly public affair, with lots of witnesses on the scene. His body was taken by the Cadmus Project, and then seized from them by the government to be given a hero's burial.
In Batman v Superman, there is almost no one around when the death of Superman takes place, and his body is apparently taken by Batman and given to Martha Kent, who buries her son in an open casket.
This rubbed some fans the wrong way, since it seemingly made it very difficult to bring Clark Kent back and allow the Man of Steel to have a human life when he returns from the grave -- but could the AC 301 reference here be used to suggest they will "bring back" Clark using some kind of narrative device that suggests Superman was somehow "in on" Clark's disappearance and funeral?
It's probably a stretch, but if true, it would address one of the bigger problems some fans had with Batman v Superman.