Is a prosecutor’s job to convict guilty people or do justice?

I have wondered about this many times: the balance between the obligation and need for prosecutor’s to put guilty people in jail and what I view as a competing obligation to do justice.  Doing justice to me means ensuring that every defendant receives adequate representation and a fair trial.  Sometimes ensuring these things might come at the expense of a conviction.  

A brutal, gut-wrenching story from Nashville, Tennessee about a man on death-row stirred these thoughts in me again.  To summarize the story, the man had sorely and shockingly poor representation in a murder case because his very capable attorney was to busy and overworked.

The primary attorney did almost nothing to defend the man including calling no defense witnesses and making an opening statement that was three paragraphs.  The attorney first interviewed his client five days prior to trial.  People familiar with the case believe that this man is on death row because his attorney did not do his job. The attorney’s performance or lack of performance was deplorable, there can be no question about it, the attorney admits it.

My question is:  Did the Judge in the case or the prosecutor notice the attorney’s shockingly poor performance?  If they noticed, shouldn’t something have been done, such as talking to the attorney or continuing the trial and allowing the man to find new counsel?  Who protects the accused when his primary defender and strongest advocate – the attorney, fails to do so?

This is where the prosecution versus justice argument boils over.  Prosecutor’s are already required to turn over evidence to the defendant that might prove the defendant’s innocence including all paperwork, witnesses and physical evidence.  Should the duty go further than that?  Should the prosecutor be required to be a fair trial advocate at the same time he is a zealously prosecuting a defendant?

I have many questions but no solid answers.  We all want our prosecutors to be zealous and aggressively try to put the guilty in jail to protect society.  However, anyone in the position of a defendant and many other people want the defendant to receive a fair trial, a right that is a bedrock principle in our country.  It is also a right I suspect is never more fully cherished than when you (or me) are in the position of defendant.

So, what do you think, should one value be elevated over the other?  I would love to hear your thoughts.