In our family, I definitely have final say over the girls' haircuts and hairstyles, because I'm the one who deals with them. At the same time, however, my husband gets input and has strong opinions about some things.
He's not fond of bangs, and he thinks that Jenny's, particularly with her straight hair, don't look great on her, so I have a feeling she's going to be growing hers out in the next few years. At least her hair grows fast! Little Charlotte's hair grows like a weed and is already halfway down her back at age 2, but she also has slightly curly hair and the most charming bangs (plus hair that is so wild that it would never stay out of her face if she didn't have bangs), so she'll probably get to keep hers for now. But while my husband might suggest this or that, or ask me to do something different, etc., he wouldn't lay down the ultimatum or do anything to the girls' hair without me, unless it were a true emergency (gum or paint in the hair, etc.).