Legal hurdles would look familiar in any new R. Kelly case By MICHAEL TARM, AP Legal Affairs Writer CHICAGO (AP) — Prosecutors will have to clear a series of high legal hurdles if they intend to charge R. Kelly and convict him, even if there's video evidence. One case illustrates the difficulties: The R&B star's own 2008 trial at which he was acquitted. At the heart of that child pornography trial