Data Science & Psychology Data Science applied to Values, Morals, Politics, & things that matter.

If you are uncertain if a criminal is innocent or guilty, is it better to err on the side of innocence or guilt?  Given that proof is continuous, not categorical, how much bias toward innocent until proven guilty should one have?  A friend of a friend recently asked is this question to a group of psychologists:

do you know if there is any evidence that conservatives would be more upset (defined loosely) by a guilty person getting away with a crime than by an innocent person being convicted of a crime? and would it be the opposite for liberals?

None of us could come up with a ready answer of a published study to this effect (feel free to let me know of one and I'll add it here), so I thought it would be useful to share a quick analysis of a few YourMorals.org questions that help answer this question.

The below question was asked on a 7 point scale, meaning that liberals (and libertarians) generally agree that it is better to let 10 people go free than to convict one innocent person, while conservatives are somewhat torn given a 10-1 scenario.

Another way to ask this question is to ask how wrong it would feel for a criminal to go unpunished.  Again, we see a similar result where liberals and libertarians are less punishment oriented, while conservatives feel it would be more wrong.  This is perhaps a gut-level intuitive rationale for the above graph.

Everyone agrees that we should punish the guilty (indeed, everyone is above the midpoint on the above scale) and free the innocent.  The issue is that we operate in an uncertain world and some kinds of errors bother some people more than other errors.

I believe a similar asymmetry drives the differences between Tea Party and Occupy Wall Street.  Most people will admit that there are lazy people who take advantage of government generosity (e.g. the prototypical welfare queen) and that there are poor people who work hard and encounter a disaster that is out of their control and deserve help (e.g. the guy who works 2 jobs that don't provide health care, and gets a chronic disease).  The question is which case bothers you most.

Similarly, there are cases of wealthy people who clearly deserve their wealth and who create wealth for others (e.g. Steve Jobs) and there are cases of wealthy people who game the system and create negative wealth for others (e.g. the aggressive mortgage bankers of the sub-prime crisis).  Is it worse to unfairly tax Steve Jobs or unfairly let the bankers keep their windfall of ill-gotten rewards?  There is no right answer to this.  I would submit that in such uncertain circumstances, we all let our intuitions lead our moral thinking, and hence we see the strong divisions we see in society.  Personally, I think it's a good thing (that the conversation is had, though not that it gets so personal and uncivil), as society needs a healthy balance between punishing the guilty and protecting the innocent.

- Ravi Iyer