According to the "Official BATMAN BATBOOK" by Joel Eisner, ABC was looking at ways to strengthen their lineup (I believe they were in last place in the network ratings at the time) when someone in the lower echelon of the programming department (a Mr. Benvegnal) suggested ABC look into the area of comic books as possible source material for 7:30 programming which was back then prime time. They had a research outfit question people in supermarkets, churches, schools, and so on which shows they'd rather see on TV. They had Superman, Dick Tracy, Batman, Green Hornet and Little Orphan Annie in that order. ABC couldn't get the rights to Superman because of the "It's a Bird, It's a Plane, It's Superman broadway show. They couldn't get Dick Tracy because Chester Gould was in some kind of peripheral negotiations with NBC, which never came to anything. (Later on after Batman became a big success, a Dick Tracy pilot was made but wasn't very good). So ABC did get the rights to do Batman and the rest, as they say, is history.