Hi Mart,
I've not seen Rendition, but I have seen the mostly excellent American Gangster.
I say mostly, because of a bit of possible shark-jumping towards the end.
I found it quite strange that Roberts, after passing his Bar exam, was the man who prosecuted Lucas in court. I've tried to research this to see if it actually happened, but have not found the answer yet.
What is interesting is that after becoming a defense attorney, Robert's first client WAS Lucas (this IS true).
So, if the film is to be believed, Roberts was the cop, then the prosecuting attorney, and then a few years later, he was Lucas' defense attorney too. Talk about confusing!