BMI, like Sony, is a recording studio. They don't regulate anything, although they do own the copyright rights to music created by some of their artists, or have distribution rights for artists that hold their own copyrights.
Copyright infringement is regulated by the Digital Millennium Copyright Act, passed in Oct 1998. www.riaa.com is another good source for information about copyright legislation. The RIAA and ASCAP are associations for studios and artists respectively.
For an alternative view on current copyright law, you might also want to look at the Free Software Foundation, particularly the philosophy section. Also the Free Music Philosophy makes for an interesting read.
(not speaking for Global, the FSF, or anyone else)