Director Ron Howard confirmed the character's identity:
I will say that was scripted and there was a lot of uncertainty as to who that character would be. So it was sort of initially written in a rather generic way. It just sort of said “Boss”. And I thought when I came in, I assumed they knew who it was and they were just keeping it under wraps. And they didn’t. But Maul was listed as one of the candidates. And I lobbied hard for that. I thought that made a lot of sense to me. I found that character to be really effective. And I knew for a fact, without asking directly and giving anything away, my son Reed who just turned 31, who’s a dedicated Star Wars fan, he’s a golfer. He’s not in the business. Dedicated Star Wars fan. I just whispered that possibility and he just thought that would be incredibly cool. And so for that generation, I thought, well that was gonna be a pretty interesting idea.
As have screenwriters Jon and Lawrence Kasdan:
Jon was a particular champion of Darth Maul. We knew that Dryden was not the top of this ladder at all, and we wanted it to be someone really powerful. But Jon was the one who said, 'It's got to be Darth Maul.