^No thanks, I already have a brain.
You seam to lack the part that should tell you when to shut up. Seriously mate, almost every other post I've seen you make you're either correcting someone, splitting some insignificant hair or coming back with some sarcy comment when you've been contradicted. It's gone way
Dunst was more Gwen Stacy than Mary Jane in her performance of the character in the trilogy while I thought Bryce Dallas Howard had a little 616 MJ in her. Nevertheless fans are fickle and protective of their favorite characters actually looking and acting like the characters they're taken from with regards to adaptions. There are scenes where Anderson has her helmet off so this is a relevant discussion if you're a Judge Dredd fan. I'll have to go back and look but I'm pretty sure that she was described as being blonde which is also a contrast to Dredd's character in the film.
I'm pretty sure she manages to loose the thing pretty early on so she should be helmetless for pretty much all her scenes. Which is consistent with the comics, Anderson and indeed most of the Judges spent most of the time while not out on street duty with the helmet off. Dredd's the only one that has it permanently stuck there.
Of course the artistic reason is it makes it a lot easier to tell uniformed characters apart when you can see their faces (aforementioned nametags notwithstanding.)