Butler has a School of Music and though it offers a BA for instrumentalists and vocal performers, only a BM is available to composition students.
Personally, I think composers may benefit more from a BA program. Composition involves development over time and does not require the hours of daily practice that instrumenalists must do. Composing is greatly enriched with studies in art, literature, history, technology, anthropology, classics- all kinds of subjects. And many BA grads get into grad school for composition. A BA music major will take composition, theory, music history, musicianship, ethnomusicology, some electronics etc. More burden is on you to compose outside of class and build a portfolio for grad applications (three pieces)which means getting performances.
If you want to do a BA with the flexibility it offers for science classes as well, you will still have many options open as your interests may change. A BM is a bachelor’s like any other, but 2/3-3/4 of your classes will be music, whereas a BA program will usually be 1/4-1/3 music. Some BM programs will entail playing an instrument, others won’t. BA programs often do not require audition or portfolio, but you can enhance your application with an arts supplement to the common application, with scores, CD, music resume, list of works, and music teacher recommendations.
If you do want a BA, usually ( not always) it really is a good idea to avoid colleges that have music schools or conservatories (at Butler composers cannot do BA’s anyway, as I said). Many of these schools will have BA’s in music in addition to the BM, and the BM’s get attention, good teachers and performance opportunities. But make sure to check this out before excluding anything- some schools are exceptions (Bard for instance, which has a BA in music and great science).
I would suggest picking a school based on size, location, academics, and “vibe” and then checking out the music. You can do composition almost anywhere. And I still think the aesthetic of the department is very important. That choice requires some sophistication on your part, so do some reading (Alex Ross’ “The Rest is Noise” for instance) and listen to a lot of music, including faculty.
p.s. Have you considered Cornell?
pps I sent you a private message