It was no secret that Jillian didn't want to register. It wasn't that she was politically opposed to it but that she didn't need the government knowing every little thing about her life. She wore a mask because she wanted to save people, not because she wanted a pat on the back or praise. She heard about the Snakes from one of her teammates and decided to take it since no one else wanted it. She suited up and flew to the scene.
Once there she manipulated the darkforce to blind some of the snakes and immobilize others. she looked over and saw a man in armor join the fray and was about to immobilize him too until she saw that he was on her side.