I think it was only mentioned once by Jasmine, but we haven't seen them. H&A still have doctors 'in charge' of whole department, like when Alex told Jasmine off because she was having lunch with Willow at the hospital. Tbh I didn't really care, but my friend who is a nurse had real issue with it, because according to her Alex should've told Nurses Manager so that they could deal with Jasmine.
But in TV shows nothing is like in the real life, and they had to have Alex and Willow meet somehow. ?
Regarding Tori and Christian, tbh I don't really know, but I assume with him being the specialist he is in charge of his specialty and Tori of hers. I don't think Tori has the power to overrule Christian's decision regarding neurology or tell him what to do. But doctors consultants should just come and go, not hang around ED.