Footage believed to have been shot in January 2008 after 50-mile chase . Beating occurs after car rolls over , ejecting unconscious man onto ground . Prosecutors found footage while preparing for man 's attempted murder trial . Comment:
Footage believed to have been shot in January 2008 after 50-mile chase . Beating occurs after car rolls over , ejecting unconscious man onto ground . Prosecutors found footage while preparing for man 's attempted murder trial . Birmingham mayor says incident recalls days of segregation , police brutality .