Well for somewhere like NYU, for example, because they have so many different schools, the MS and PhD programs may each fall under different schools, in which case, the adcom is likely different. For example, getting a MS at NYU in biology is associated with the "Graduate School of Arts and Science" but if you were going for a PhD in "Cellular and Molecular Biology", that would be associated with the "Sackler Institute". If you investigate the schools and see if there is overlapping faculty, that will help you figure out if there is a possibility of any part of the adcom being the same.