While waiting for results of hospital tests on the ankle he had injured in junior college , Robinson got on an Army bus with a fellow officer 's wife . Although the Army had its own unsegregated bus line , the bus driver ordered Robinson to move to the back of the bus . While awaiting results of hospital tests on the ankle he had injured in junior college , Robinson boarded an Army bus with a fellow officer 's wife ; although the Army had commissioned its own unsegregated bus line , the bus driver ordered Robinson to move to the back of the bus .