De IMDb :
When the series was expanded from Justice League to Justice League Unlimited, producers considered adding Batman's sidekicks, Robin, Batgirl, and Nightwing.
However, DC Comics turned them down, because the Robin/Dick Grayson role was being used on Teen Titans.
Havia / é algo chamado "(Bat) -Embargo" :
a decision to keep certain DC characters exclusive to certain shows across the television and film medium.
Bruce Timm , o homem por trás de Liga da Justiça e Liga da Justiça Ilimitada disse sobre o Bat-Embargo :
... to tell you the truth, as much as I […] love those characters, I don’t really miss [them] all that much. It’s not like we don’t have tons of other interesting characters to play with.
If I were doing an actual Batman show, and not allowed to use those characters, yeah, that’d be pretty galling, but Batman’s only one ingredient in the Justice League’s brew. The Bat-clan aren’t really essential in any way to the current show ...
-
embora ,
At one point during the later series Justice League Unlimited, an episode featuring Batgirl was discussed. ... The episode was never produced as the rights to the Batgirl character were not held over and were being used by the team on The Batman at the time
No entanto, no episódio Grudge Match eles contornaram o Bat-Embargo :
Dick Grayson has a blink-and-you-miss-it cameo as Nightwing, shown watching from a rooftop as Canary and Huntress drive their way into Blüdhaven.