[jeffcoat]

I think I know what you're getting at, but the problem here is that prosecutors have some discretion.

The chain of thought that goes

  I only prosecute worthy cases

  => I picked those cases because these people are guilty,
      and need to be convicted for the good of society 

  => my conviction rate is exactly the same as my 
     'I made a better world' rate.

must be very tempting. Wrong, but tempting.

[Tomte]

It's a "damned if i do damned if i don't" situation.

If the conviction rate is low, people on the Internet say that the prosecutor is just harassing innocent people.

If the conviction rate is high, people on the Internet say that the judges rubber-stamp whatever the prosecutor throws at them.

I've never seen anyone say "sounds about right" when any conviction rate was posted.

[Edit: Killed the last sentence, as per site guidelines]

[jacquesm]

Exactly. So how about 'if you are concentrating on the conviction rate then you're doing it wrong'?

It's like the story about communist strategies for optimizing production, making a metric by which you measure performance in some hard to quantify domain is going to give you an industry optimizing for that metric which will have a ton of un-intended consequences.

The goal of a prosecutor should not be to aim for a certain conviction rate (either high, low or anything inbetween) and the goal of a justice system should not be related to any such metrics either.

The right way to go about this would be to establish guilt or innocence without regards to any metrics and with a relative disregard for the cost of such an operation because the number of criminals is low compared to the number of non-criminals and should err on the side of caution.