Since the release of Batman V Superman: Dawn of Justice earlier this year, fans have been theorizing over Robin's role in the DC Extended Universe, both past and in the future. In one particular Batman V Superman scene, Bruce Wayne (Ben Affleck) stands before Robin's suit - which is enclosed in a glass display case and covered in Joker-style graffiti, making it clear that his death came at the hands of the Clown Prince of Crime (Jared Leto).
Beyond that though, Robin's backstory is left open to speculation in both the theatrical cut and the "Ultimate Edition" version of Batman V Superman. Like other ambiguities in the film, Robin's demise was left as a mystery for the audience to solve. Now that the next DCEU installment, Suicide Squad has come along, we're still waiting for some clear-cut answers about what happened to Batman's young sidekick in this movie universe.
Suicide Squad writer/director David Ayer has now discussed that very issue with Empire:
"This is sort of my personal thing and maybe less about a larger connection. But Joker killed Robin and Batman basically smashes his teeth out and locks him up in Arkham Asylum. It’s in the asylum where Joker would have done the ‘damaged’ tattoo as a message to Batman saying, 'You’ve damaged me. I was so beautiful before and now you’ve destroyed my face.' That’s where the grill comes from."
Joker's forehead tattoo and shiny silver grill in Suicide Squad now make more sense as far as serving an actual purpose goes (as opposed to just being a stylistic addition to the iconic villain in Ayer's film). While some fans may've felt that Leto's Joker was just trying to be "too cool" with all of his tattoos and golden accessories in Ayer's DCEU movie, his "damaged" tattoo has a greater significance when you approach it from Ayer's perspective on the matter (be it considered "canon" to the DCEU or not).
Warner Bros. has confirmed the "Robin" in the DCEU is in fact Jason Todd, the second person to take the mantle of Robin, following Dick Grayson. Todd died at the hands of the Joker in the famous comic story “A Death in the Family”. The event emotionally destroyed Wayne, who struggled with guilt because he was unable to save Robin. Todd was later brought back to life as the violent anti-hero Red Hood and eventually crossed paths with Batman again. This goes along with the theory that the solo Batman flick (which Affleck is co-writing and directing) will take on the Red Hood story arc.
Will we ever see Jason Todd as Robin in the DCEU? We really have no idea. But one thing is for sure, fans of Jared Leto's Joker and even Leto himself are vying to see more of the twisted Clown Prince in one way or another. It might have also been conducive to the franchise if audiences actually saw a scene of Joker getting his teeth knocked out when he's captured by Batman (instead of Ayer just describing it to us after the fact).
Suicide Squad is in theaters now. Wonder Woman opens on June 2, 2017; Justice League on November 17, 2017; Aquaman on July 27, 2018; an untitled DC Film on October 5, 2018; Shazam on April 5, 2019; Justice League 2 on June 14, 2019; an untitled DC film on November 1, 2019; Cyborg on April 3, 2020; and Green Lantern Corps on July 24, 2020. The Flash, the Batman solo movie and Man of Steel 2 are currently without release dates.