can a former employer tell a future job prospect , not to hire me because there was theft at his business although unproven and not to hire me ?

on 07/26/12 I told my boss i wanted to transfer back to michigan after my fathers death, I told him I would stay until 10/16/12 to end my lease at my apartment, he agreed to this. on 07/27/12 he let me go claiming someone was stealing from him. he has no proof of this because it did not happen. on 08/21/12 I interviewed with another franchise and agreed to start work on 09/01/12 1 hour after my interview they called me back and told me they no longer needed me. they told me when they called my ex employer for a reference he told them that I was involved in stealing and shortages in the register and that is why he let me go, and suggested they not hire me.